DEPARTMENT OF LANDS AND SURVEY: SURVEYS (ANNUAL REPORT ON).

Appendix to the Journals of the House of Representatives, 1919 Session I, C-01a

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1919. NEW ZEALAND.

DEPARTMENT OF LANDS AND SURVEY: SURVEYS (ANNUAL REPORT ON).

Presented to both Nouses of the General Assembly by Command of His Excellency.

The Surveyor General to the Hon. Minister of Lands. Sir,— Wellington, 14th July, 1919. I have the honour to present herewith the report on survey operations for the year ended 31st March, 1919. I have, &c, E, 11. Wilmot, Surveyor-General. The Hon. D. H. Guthrie, Minister of Lands.

EEPOET. This report deals with survey operations for the year in a general way only, leaving details to be found in the tables attached and in the reports supplied by the Chief Surveyors filed as departmental records. Under the heading " Rural Surveys " in Table B, an area of 302,369 acres is shown as completed work, against 343,525 acres for last year. The decrease of 41,156 acres is due partly to the small field staff available, and partly to the fact that so many of the surveyors have been employed on the surveys of small estates for soldier settlement instead of on large blocks of Crown lands. The area of Native lands surveyed during the year for the ame reason shows a decrease from 271,481 acres to 241,927 acres. The cost of rural surveys remains the same as last year —Is. 6d. per acre—but Native surveys have gone up Id., being this year Is. 7d. per acre. The increase is in the cost of the work done by private surveyors, which amounted to 95 per cent, of the whole, and is no doubt accounted for by the difficulty of obtaining labour and the consequent high wages paid. A summary of the work executed during the year will be found in Table A.

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Table A.

Table B.

Major Triangulation. No field-work has been done, and further field data will be required before the computation-work can be proceeded with. In an appendix will be found an interesting report by the Chief Inspector of Surveys on the 8 in. micrometer theodolites used. Minor Triangulation. Although all work of this class except what is absolutely necessary for the proper location of and check on settlement-work has been stopped, 146,516 acres are shown under this heading, at a reasonable cost of under fd. per acre. The only districts in which this class of work was undertaken were Auckland and Nelson. Topographical. Under this heading 345,845 acres, at a cost of 0-92 d. per acre, are shown. This work is done as a preliminary to settlement surveys, and this year was undertaken in Auckland, Otago, and Nelson. Standard Surveys. Work on these very useful surveys has been continued by Messrs. C. A. Mountfort, W. T. Neill, and H, M. Kensington, in Napier, Dunedin, and Auckland respectively. In Napier and Dunedin very

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Class of Work. Area. Average Cost. Total Cost. Triangulation, by staff surveyors Topographical, by staff surveyors Rural, by staff surveyors Rural, by staff surveyors (costs unobtainable) Rural, by licensed surveyors Rural, by licensed surveyors (costs unobtainable) Village and suburban, by staff surveyors Village and suburban, by staff surveyors (costs unobtainable) Village and suburban, by licensed surveyors Town, by staff surveyors Acres. 146,516 345,845 289,063 45 10,486 2,775 0'67d. per acre 0-92d. l.-50s. £ s. d. 414 13 5 1,327 2 11 21,714- 12 8 2-15s. per acre 1,128 18 9 944-87 257 15-00s. per acre 712 9 6 Town, by licensed suiveyor.s 107 172-74 (in 92 sections) 38-20 (in 115 sections) 13,119 193,744 35,064 14-53s. per acre 37-77s. per section 18-6s. 77 15 0 173 15 5 106 18 9 Native Land Court, by staff surveyors Native Land Court, by licensed surveyors .. Native Land Court, by licensed surveyors (fees paid by applicants) Mining, by licensed surveyor i (fees paid by applicants) 18-35d. per acre 19-35d. 1,003 2 11 15,623 10 11 992-5 Roads, by staff surveyors Roads, by staff surveyors (costs unobtainable) Roads, by licensed surveyors Roads, by licensed surveyors (costs unobtainable) Miles. 124-33 3-25 3-78 5-7 £22-46 per mile 2,793 10 9 163 14 0 £43-30 per mile

Land District. Rural Surveys. Nativo Land Court Surveys. Auckland Hawke's Bay Taranaki Wellington Nelson .. Marlborough Westland Canterbury Otago .. Southland Acres. 73,081 23,099 19,711 8,478 12,493 1,849 3,238 67,427 85,484 7,509 Acres. 138,499 49,496 26,264 16,469 5,228 3,732 717 1,522 Totals 302,369 241,927

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little now remains to be done, but in Auckland, owing to the growth of the city, many miles of streets are still without standard blocks. The high standard of accuracy so necessary in this class of work has been well maintained by the experienced officers above mentioned. After completing the Napier work Mr. Mountfort took up rural standard surveys in the neighbourhood of Feilding, where the trig, stations had in many cases become useless for checking work on account of the views between them, and from them, to check-points having become blocked by plantations and buildings. Settlement Surveys. Of these, which comprise Crown lands, land for settlements, and land for discharged soldiers, the bulk appears under the heading of " Rural " in Table A, the acreage there shown, being 302,369 acres, while the remainder includes village and suburban and town lands totalling 1,309 acres. In Table B the rural acreage has been allocated to the various land districts. Native Surveys. During the year staff surveyors completed the survey of 13,119 acres, while 228,808 acres was surveyed by private surveyors. The area surveyed in each land district is given in Table B. The surveys under this head have mostly been subdivision surveys of blocks of which the periphery surveys had been already completed. Gold-mining Surveys. The area returned under this heading is very small, being only 992 acres. The surveys were made by private surveyors, the fees being paid by applicants. The cost per acre cannot therefore bo given. Coal-mining Surveys. No surveys of coal-mining areas were made. Inspections. There being only one Inspector, the work of inspection has been carried on by Chief Draughtsmen and staff surveyors. In consequence there has not been so much of this very necessary work done as I could have wished. As pointed out in previous reports, absence of inspection has a tendency to induce carelessness in some surveyors, the more so as it is difficult for them to get good field hands. Generally speaking, I am pleased to note that the result of the inspections made has been to show that satisfactory work is being done, though an amount of remissness and carelessness has been revealed sufficient to show that more inspection-work is urgently required. Proposed Operations for 1919-20. Trianyulation. —Owing to the depletion of the field staff and the need for economy during the war the major triangulation was for the time being discontinued, but it is hoped that a start may again he made some time during the coining year. No minor triangulation save such as may be absolutely necessary for the connection and control of settlement surveys will be undertaken. Standard Surveys. —These surveys will probably be principally carried out in Auckland, though an endeavour will be made to organize a staff for this work so that in the near future it may be undertaken in a more comprehensive manner. The approximate cost of this class of work is about £50 per mile, and part of this cost —in ordinary cases two-fifths—is borne by the local body. The great value of these surveys is recognized by the City Councils of Auckland and Dunedin (in which cities for years past standard-survey work has boon in progress), and they are only too pleased to contribute on these terms. In addition to the standard survey of Auckland, which will be continued by Mr. Kensington, the rural standard-survey work will be continued by Mr. C. A. Mountfort. In future all standard surveys will be controlled direct from Head Office. Topographical Surveys. —Under an arrangement with the Defence Department the work initiated by Colonel Gibbon, of publishing topographical contour maps of the Dominion, is to be carried on by this Department. Up to the present it has not been possible to do so, but 1 hope during the ensuing year to be able to get together a small staff and make a beginning. The maps will be very useful to the travelling public, especially to motorists, and should meet with a ready sale, by means of which a large portion of the cost of production will be covered. ■ Settlement Surveys. —At the close of the year there were in the hands of the staff and temporary surveyors 596,856 acres of settlement lands and 75,670 acres of Native lands, while in the hands of private surveyors there were 30,826 acres and 287,977 acres respectively. The allocation of this work among the several land districts is shown in Table 4. As is always the case, and more particularly so at the end of last year, for reasons already given, these figures include a large acreage of which the field-work has been completed, but of which the mapping will not be finished till July or August, during which months many of the surveyors will be called in from the field to the office. In addition to the allocated work, Chief Surveyors had in sight 13,180 acres of settlement land and 3,970 acres of Native lands to be allocated later on. The work now in hand, together with that as yet unallocated, and the survey o! estates that from time to time will be acquired for soldiers' settlements and for ordinary settlements, and of Crown lands to be offered for settlement, will occupy most of the staff surveyors fully for the ensuing year. As the urgency of providing land for discharged soldiers increases, it will probably be necessary to supplement the efforts of the staff by placing contracts in the hands of private surveyors.

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Head Office Draughting Staff, The calls for work for other Departments during this year have been fully tip to the usual volume, and in spite of a diminishing staff have been met, although with difficulty, Probably the map-work of the Department for publication has never been at so low an ebb, both in quantity and quality, as at the present time. Reproduction of maps has had to be made without revision as a temporary expedient, and the slowness with which printing has proceeded has prevented many maps from being put in hand at all. Originals for new four-mile maps for the South Island have been completed and await printing, and the City of Wellington map has been brought date. Town plans have continued to come in, number has been maintained, and no doubt will now increase with, the change from war conditions. A general reorganization and overhaul of the publications will be carried, out as soon as the projected replacement of staff can be effected. Draughtsmen's Examination. This examination was held on the 3rd September, 1918, when ten candidates sat, two of whom, Mr. Saunders and Mr. Elvy, obtained second-grade certificates, and Cadet Nightingale passed the elementary stage, while several others have but one subject to complete to obtain this grade. Draughtsmen generally hardly seem as yet to realize the importance of this examination to their future prospects, more especially the younger men, the. older men usually being already otherwise qualified for passing the salary bar of £300 per annum. Surveyors' Board. Examinations were held in September, 1918, and March, 1919. • At the former eleven candidates sat, two passing ; and at tho March examination four sat and two passed. The return of many pupils and cadets from military service will bring a considerable increase in the number of candidates for the next ensuing examinations, and certain concessions have been agreed upon by the Associated Boards for this class of candidates. Tidal Survey. The work for the year comprised the predictions for the year 1920 at the ports of Auckland and Wellington, and the completion of an additional harmonic analysis to determine the tidal constants at Auckland. The computations were carried out, as in former years, by Messrs. Gillespie and Williams. The mean sea-level at New Plymouth was determined from a year's record by an automatic tidegauge, and was referred to permanent bench-marks. 4\.n inspection of the tidal stations at Auckland, New Plymouth, Wellington, Lyttelton, Dunedin, Bluff, and Westport was made by the Chief Inspector, and levels wore taken to connect each of the automatic tide-gauges to a permanent bench-mark. The work connected with the preparation of the necessary data to enable a tide-table to be prepared for the year 1921 for the ports of Auckland, Wellington, Lyttelton, Dunedin, Bluff, and Westport was commenced, and will be continued, during next year. Dr. C. E. Adams, who was previously in charge of this work, having been promoted to the position of Government Astronomer, the control of the tidal survey was entrusted to Mr. W. T. Neill, Chief Inspector of Surveys, whose report appears in an -appendix hereto. Magnetic Observatory. The work of the Magnetic Observatory at Christchurch has been carried on by Mr. H. F. Skey, B.Sc. Continuous records of the magnetic elements for the year have been obtained from the selfrecording instruments at the Observatory, and also at the substation at Amberley. The Milne seismograph No. 16 has been kept in operation. In addition to the routine work of the Observatory meteorological observations have been taken and supplied regularly to the Dominion Meteorologist and to the local newspapers. In Appendix II is given the hourly values of the magnetic declination and horizontal force, the vector diagrams, and diagrams showing the magnetic curves for the year. In the report by the Chief Inspector of Surveys (Appendix 1) will be found further details as to the work of the Observatory. If it is desired that the work of this Observatory shall be brought up to a proper standard of usefulness it will be necessary to increase the staff, and in any case it is essential that an understudy to the Director (Mr. Skey) should be appointed. General. During the past year the staff, both field and office, suffered severely by reason of deaths, retirements, and enlistments. The roll of honour has had added to it the names of Surveyors H. F. Edgecumbe, H. E. Girdlestone, and P. C. Gannaway ; Survey Cadets A. E. R. Bagnall and A. D. Bines ; and Draughtsmen T. L. Folley and 0. D. Pearce. There also passed away after a long and painful illness, borne with wonderful fortitude, Mr, F. A. Thompson, Chief Surveyor of Nelson ; Mr. A. N. Harrop, Chief Daughtsman. Ilokitika, died suddenly ; Surveyor R. M. Mclvor was a victim of the influenza epidemic; and Cadet W. E. Gourley met his death by accident. The retirements were Mr. H. A. Farquhar, who was for many years senior draughtsman in Head Office, and Mr. A. M. Roberts, one of our surveyors. The enlistments comprised two surveyors, one draughtsman, and two draughting cadets. One draughtsman was also dismissed. The Department has thus lost permanently thirteen officers, and temporarily five officers. On the other hand, lam pleased to be able to report that three surveyors, four field cadets, and four draughtsmen have

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returned from the front, most of them towards the close of the. year, several being still on departmental leave of absence. At the close of the year there are still absent with Forces five surveyors, five field cadets, two surveyor's assistants, eighteen draughtsmen, and two draughting cadets —in all thirty-two. It is anticipated that these will all return during the next six months. During the coming year there will be numerous retirements of officers who have reached the age-limit, and of superannuated officers "who have been kept on during the war, and it will be necessary to provide for bringing the staff up to normal by appointing a considerable number of cadets, both field and draughting, and by the appointment to permanent positions of certain temporary officers who have proved themselves capable men. It will also be necessary to employ temporary men during the year. In all appointments it is desirable, that where practicable preference shall be given to returned soldiers. It has appeared to me for some time past that a reorganizing of our office staff is very desirable, and accordingly I submitted a scheme which would in my opinion secure greater economy and efficiency, and, while not depriving the field staff of their recognized right to have a chance of rising to the higher positions in the Department, would permit of draughtsmen also rising to positions of responsibility and consequent adequate remuneration. Though the scheme was approved by the Public Service Commissioner, it has not been deemed feasible that it should be brought into operation while the war conditions still prevail, out 1 hope that as soon as things become comparatively normal it will be given a trial. In conclusion, I am pleased to place on record the appreciation by the various Chief Surveyors of the manner in which their officers, both permanent and temporary, have carried out their duties during the year, and I desire to convey my thanks to the whole of the Survey staff for their good work during a very trying period.

Table 1. —Return of Field-work executed by Head Office Staff from 1st April, 1918, to 31st March, 1919.

Standard Surveys. Bural Standard Surveys. Laud District. Completed. In Progress. Completed. In Progress. Otlier Work. Auckland Miles Cost Miles Cost ml8S - per Mile. MU6S - per Mile. 69 33 40 £ 39-48 50-86 48-24 Mild, Cost Miles Cost MIies - per Mile. MIIes - per Mile. £ £ s. d. 169 15 5 43 30 43 15 10 Hawke's Bay Otago Note.—The average cost of the standard surveys is ab' jut, Hi 10s. per mile.

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Table 2. —Return of Field-work executed by Staff and Contract Surveyors on Lands administered by Lands and Survey Department, from 1st April, 1918, to 31st March, 1919.

Minor Triangulation. Topography. Rural. Village and Suburban. Town. Koads, &c. Total Cost of Completed Work from 1st April, 1918, to 31st March, 1919. Land District. Other Work. Acres. Cost per Acre. Acres. Cost per Acre. Acres. Cost per Acre. Acres. Number of Sections Cost per Acre. Acres. Number Cost of per Sections Section. Miles. Cost per Mile. d. 0-76 d. 0-74 s. 2-3 83 s. 11-17 35 s. 44-7 101-75 £ 22-68 £ s. d. 2,424 10 10 £ s. d. 15,599 0 10 Auckland 32,666 261,268 71,240 7 159-02 Hawke's Bay 23,099 1-85 849 4 0 3,339 15 8 Taranaki 19,711 I 4-35 , 136-47 14 17-94 j I 102 21-97 4-13 I 6-38 39-0 36-18 331 3 4 2,692 2 2 Wellington 8,478 2-36 ' 282-4 30 5-44 31-92 331 18 8 1,750 8 5 Nelson 113,850 0-65 8,985 6-8 12,493 2-57 | 162-0 50 15-18 19 69 21-81 2-0 22-5 294 7 5 35 10 6 4,361 5 0 962 5 4 Marlborough 1,849 2-94 4-6 219-0 1 | 303-75 3-25 0-25 ! | 8-62 20-0 Westland 3,238 12 25-5 1 107 9 10 945 3 7 67,427 - Canterbury 0-28 09 23-8 1,333 16 10* 35 8 6 555 14 2 2,906 9 3 2,975 10 9 1,560 16 4 Otago 75,592 0-9 85,484 0-53 98-0 I 4 15-0 7-5 1-95 4-0 65-36 Southland 6,256 4-27 680 21 16 95 Means and totals.. 146,516 0-67 I 345,845 0-92 299,275 138 14-86 210-94 6,299 4 1 37,092 17 4 1-52 , 1,048-87 207 27-12 128-11 23-08 licensed surveyors (costs unobtainable) 2,820 257-0 84-25 •• 8-95 j 302,095 1,305-87 295-19 , 137-06

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Table 3. —Return of Field-work executed by Staff and Contract Surveyors on Lands administered by other Departments from 1st April, 1918, to 31st March, 1919.

Land District. Run Cost per Acre. Villagi and Subi ■ban. Town. Cost per Miles. Section. Soadi i, Ac. Native Land Survi Number of Subdivisions. Cost Number Cost per Acres. of per Acre. Sections. Acre. Mining. Other Work. Total Cost of Completed Work from 1st April, 1918, to 31st March, 1919. Acres. Acres. Number of Sections. Cost per Acre. Acres. Number of Sections. Cost per Mile. Acres. s. s. d. 19-00 £ s. d. 221 19 4 £ 8. d. 8,396 4 5 Auckland Hawke's Bay 104,499 801 49,496 208 16-39 3,379 13 11 Taranaki 26,264 279 20-83 .. 2,279 13 0 Wellington 16,469 182 24-65 1,692 0 0 Nelson i 5,228 13 12-26 .. 267 4 3 Marlborough 3,732 28 27-00 419 17 9 .. Westland i . ■ Canterbury 653 43 83-20 226 7 11 .. | - Otago i ..I .. Southland 274 2-5 3 1 73-3 1,522 14 29-57 232 2 11 Means and totals 274 274 2-5 3 1 73-3 206,863 1,568 19-29 221 19 4 168,893 4 Licensed surveyors (costs unobtainable) 35,064 992-5 8 ! 241,927 992-5

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Table 4. —Return showing Surveyors employed and the Work on Hand on 1st April, 1919.

Table 5. —Principal Classes of Office-work done from 1st April, 1918, to 31st March, 1919.

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Sur -eyors employed. Work on Hand. Chief Surveyors. «" Contract. «o tt-io Nativement." ToWU - land Sur " Staff. Land District. I Trig. Topography. Roads. H. M. Skeet W. F. Marsh G. H. Bullard .. G. H. M. McClure H. D. MoKellar .. H. J. Lowe R. S. Galbraith .. H. D. M. Haszard, F.R.G.8. R. T. Sadd T. Brook 12 4 3 2 4 6 2 6 36 7 2 7 Si Auckland Hawko's Bay Taranaki Wellington .. Nelson Marlborough Westland Canterbury .. Sq. iVIiles. 63 42 100 !q. Mill 63 42 100 Acres. Acres. 85,663 30,865 44,600 8,196 31,526 6,300 5 121,031 Acres. 691 Acres. 57,823 33,275 4,354 41,465 Miles. 120 7 5-9 5-2 15.5 i l 11 145 1 3 1 1 1,000 13 - 4 1 '.'. 2 Otago Southland .. 265,894 *27,776 404 326 "3-5 Total staff surveyors 34 10 10 63 205 205 621,856 836 138,647 170-1 * Also 400 acres jf sawmill areas.

District. Plans pli ■o . I 81 la iced on Insl of Title. g o a eo truraents s o I ll I .9 II O ft si rt o 1J « a I 1 to i Maps drawn. ti j I «l • Vh "21 § a Lithos sold. 11 1 1 m S « 3 • Luckland lawko's Bay ?aranaki Vellington Poison .. larlborough Vestland Canterbury Hago .. louthland 8,484 148 154 350 280 110 125 381 484 295 3,374 1,624 1,037 2,742 361 150 86 2,367 1,224 818 1,442 2,975 1,084 48 158 2,449 913 2,992 2,176 137 1,165 505 281 368 117 61 56 251 134 76 165 505 281 368 117 fll 5 if30 1 175 3 3 7 312 £ s. d. 98 .. 162 19 8 17 .. 46 7 6 1 7 7 31 11 10 3 6 .. 11 5 0 5 10 .. 24 12 2 2 3 .. 4 9 6 2 2 .. 8 6 6 7 .. 45 8 10 5 14 .. 66 13 1 6 17 .. 29 15 6 254 22 127 61 56 I 5 63 1,499 960 595 251 134 76 L I 484 5 250 Totals 10,811 13,783 6,110 ill,721 3,014 1,444 24 181 431 9 7 * Revised.

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APPENDIX I. EXTRACT FROM REPORT BY W. T. NEILL, CHIEF INSPECTOR OF SURVEYS. Triangulation. The field-work of the major triangulation of the Dominion is at present held in abeyance, and, as a systematic reduction of the observations and the computation of the work, cannot be commenced by the office staff until further data are available, no progress has been made with this work except the examination of the horizontal circles of the two 8 in. micrometer theodolites by Troughton and Simms,' which were used on this .triangulation, This was effected by a harmonic analysis of the readings of the graduated limb by the two opposite microscopes at each 10° division, and has for its object the determination of (1) the eccentricity (E), (2) the point on the graduated circle of the line of no eccentricity (c), (3) the angular distance between the opposite microscopes (180° j- (!), (4) the mean uncertainty of any one residual. If the centre of rotation of the vertical axis does not coincide with the centre of the graduated limb, the differences of the readings of the, opposite microscopes at each division of the limb will range, by a-regular periodic law, from a, vanishing nothing to a, maximum between the points tin the limb indicated by the line of no eccentricity and 90° on each side of it. The variable periodic quantity represented by the difference of the readings of opposite microscopes can be expressed by the formula P = B sin (Z + c) and as the microscopes may not be exactly tBo° apart a constant 0 added to the above, formula gives p = E sin (Z + c) + (J = C + A cos Z-f B sin Z if A = E sin <r, B = E cos c, where Z is an angle found by dividing the circumference of the graduated limb by the number of observations, which is 36 in this case. Four readings of the graduated limb at, 90° apart will suffice to determine the three unknown quantities C, E, and c in the above formula ; but in order to determine the eccentricity with greater accuracy, and to eliminate errors in reading and accidental errors of graduation, the circle readings at each 10° division are used. Each reading of a pair of opposite microscopes furnishes an equation of condition as above, and from these 18 equations the most probable value of the eccentricity is deduced by the method of least squares, The results for theodolite No. 218 are—E = 1-53" ;e= 0" 05'; G= — 17". The angular distance between the microscopes is therefore 179° 59' 43". The sum of the squares of the 36 residuals / 530-98 is found to be 530-28". The mean uncertainty of each is therefore -fc V—- = ± 3-89", and mean error of reading of one microscope == -fc 3-89"/ v 2 = -fc 2-75. For theodolite No. 219 the results are—E = 3-53" ; c = 103° 12'; C -23". The angular distance between the microscopes is therefore 179° 59' 37". The sum of the squares of the residuals is found to be 166-84". The mean uncertainty of each is therefore ± V = ± 2-18", and mean error of reading of one microscope = -fc 2-18"/ v 2 = + 1-54". Tidal Survey. During the first part of tl c year Messrs. Gillespie and. Williams prepared the tide-tables for 1920 at the ports of Auckland and' Wellington. The method of computing the predictions was that which was introduced by Dr. Adams, a brief description of which, is given in the annual report for 1910-11, and a more detailed account in Appendix No. 7, Part IT, U.S. Coast and. Geodetic Report, 1894, under the title of it " Manual of Tides " (Chapter V, page 183), by Rollin A. Harris. The heights and times of high and low water were checked at intervals of a, lunation by the formula given by Sir G. 11. Darwin iti the Admiralty Manual of Scientific Inquiry, page 89, and the diurnal inequality was examined to set! that it followed the same rule as shown on the tide-gauge records. The diurnal inequality is a portion of the lunar tide which, depends, at a given port, wholly upon the declination of the moon, the effect being a difference in height of the alternate tides when the declination of the moon is north or south of the Equator. A simple explanation of this phenomenon is afforded by the equilibrium theory of the tides worked out by Newton. This theory is not entirely satisfactory, and in some respects it is inaccurate ; nevertheless it furnishes a guide for the discussion of tidal observations, and its usefulness in explaining some of the peculiarities of the tides is generally recognized. Referring to Fig. 1 : E and M are the positions of the sun and new moon with respect to the Equator AB on 21st December, 1911. The shaded portion represents the form of the ocean due to the combined attractions of the disturbing bodies. At a port P in the Northern Hemisphere it is apparent that there is a difference in the height of the tide at P, and twelve hours later at P\ and that in both hemispheres the difference increases with the latitude, but at ports on the Equator the successive tides are equal. When the new moon is on the meridian of a given place the tide under the moon occurs in the daytime, whilst the tide opposite the moon is the night tide. This

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gives, in the Southern Hemisphere, when the moon's declination is south, the day tide at H higher than the night tide at H l . Seven days later when the moon is on the Equator the day and night tides are equal in height (Fig. 2) at all ports. Again, in fourteen days from the new moon the position of the moon is at M 2 (Fig. 1), and it is now full moon, during this interval of time, since the moon transits about fifty minutes later each day, the morning tide at the beginning of a lunation becomes the night tide at the end of it. Further, it consequence of the inclination of the plane of the Equator being greater than the inclination of the plane of the moon's orbit to the place of the ecliptic is, for the Southern Hemisphere, that new moon occurs in the summer months south of and during the winter months north of the Equator, as is obvious from Fig. 3, which shows the relative. positions in June and December. These considerations give a general rule for the diurnal inequality as follows : That in both hemispheres the day tides are highest in the summer, and the night tides in the winter. The tides on the New Zealand coast follow the general rule, but there are places where the diurnal inequality sometimes becomes so large that there is only one tide in the twenty-four hours, and at Singapore, although this port lies close to the Equator, the diurnal inequality is very large. For the future, the computation of the predictions will not be continued by the computing division at this office. Arrangements have been made to have the curves for six ports —viz., Auckland, Wellington, Lyttelton, Dunedin, Bluff, and Westport—run off by the tide-predicting machine at the National Physical Laboratory, England. The computing stall' at this office will perform the analyses for these ports annually to determine the tidal constants required for setting the machine. The harmonic analyses involve an enormous amount of numerical calculation. By the introduction of the printed computation forms the work is performed in a systematic and mechanical manner, but as it is found that certain abridgments of the numerical work can be introduced without impairing the accuracy of the results a certain amount of saving will be made in future reductions. The tidal station at New Plymouth was visited, and the mean sea-level lias been derived from the records of the automatic tide-gauge for a period of one year. Inspections of the tidal stations at Auckland, Wellington, Lyttelton, Dunedin, Bluff, and Westport were made, and the automatic tide-gauges connected by levelling to standard tide-poles and to permanent bench-marks at these ports. My thanks are due to the Harbour Board authorities at these places for assistance in this part of the work. A comptometer computing-machine was installed in the computing division during the year. Magnetic Survky. It is now twenty years since the field-work of the Magnetic Survey was undertaken in the Dominion, and in order to detect the secular changes in tho magnetic elements it is desirable that a number of the original stations, particularly those in the immediate vicinity of the seaports, should be reobserved. The Magnetic Observatory at Hagley Park, Christchurch, and the substation at Amberley, were visited in connection with a general inspection last March. The work of the observatory in connection with the running of the recording instruments has been continuous, and valuable records of the magnetic elements have been secured. The measurement of the curves and the reduction of the results for publication has fallen into arrears, principally on account of the observatory being understaffed. Prior to the war full tables of the hourly values of the declination and horizontal force were published in the annual report of this Department, but since 1914 the only results published were the monthly means for 1915 and 1916 of these elements and the seismological records for 1915 in the New Zealand Journal of Science and Technology. The full records together with the other arrears mentioned will soon be ready, and will be published when the present positions with respect to shortage of paper is relieved. The mean annual value's of the magnetic elements as far as they are available at present are shown in the table below:—

Table of the Mean Values of the Magnetic Elements at Christchurch Observatory.

The mean variation of the declination for the period 1902-18 is found to be increasing at the rate of 2-54' per annum.

Date, Declination 15. of N. Annual Change, Horizontal Force. Annual Change, Vertical Force. I Inclination South. Annual I , Change. Date. 1902 1903 1904 10 15-1 10 18-3 10 21-8 + 3-2 -I- 3-5 C.G.S. Unit. 0-22094 0-22669 0-22044 Y - 25 25 C.G.S, Unit, i y 0-55277 -|- 9 0-55286 -|- 19 0-55307 07 40-8 67 42-3 07 111 + L5 + l-S 1902 1903 1904 1910 1911 1913 10 37-0 10 39-0 10 44-0 + 2-63 + 1-4 4- 2-5 -!- 0-8 0-22511 0-22494 0-22449 - 22 - 27 - 23 - 35 4-28 0-55474 + 23 0-55497 0-55478 4- 40 07 54-8 67 56-2 67 58-2 + 1-78 ; -)- 1-4 [ 2-0 i 1910 1911 1913 1914 1915 1910 16 44-8 16 47-0 16 49-8 + 2-2 + 2-8 + 3-2 + 0-22414 0-22387 0-22355 -27 - 32 - 27 -I- 2 ] + 1-65 ] 1914 1915 1910 1917 1918 16 53-0 10 55-8 2-8 0-22328 0-22305 - 23 0-55486 + 34 0-55520 68 04-8 68 06-7 + 1-9 1 ] | 1 1917 1918

11

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APPENDIX No. 11. MAGNETIC OBSERVATORY, CHRISTCHURCH. By H. F. Skey, B.Sc. During the year the Adie magnetographs at Christchurch and the Eschenhagen magnetographs at Amberley have been kept recording, and tallies of the values at each hour of the year 1918 have been prepared from the resulting magnetograms for magnetic declination and magnetic horizontal force. Seasonal and yearly vector diagrams and mean monthly, seasonal, and year mean diurnal variations are shown in plotted curves. The increasing mean diurnal range is shown on the monthly diagram for the years 1917 and 1918. The customary meteorological observations have been made daily, and published for public information. Milne seismograph No. 16 has been kept in good working-condition throughout the year, and the seismograms developed, but pressure of work has prevented the completion of the measurement of the records. The elimination of accidental errors iv the vast amount of figuring involved in the compilation of the tables of hourly values has this time taken much longer than usual. The resulting mean values for 1918 are as follows: — Magnetic declination .. .. .. .. .. 16° 55-7' E. of N. Magnetic horizontal force .. . . .. . . 0-22304 c.g.s. unit. Magnetic inclination . . .. . . .. .. 68° 06-7' S. Northerly component .. .. .. .. .. 0-21338 c.g.s. unit. Easterly component .. . . .. . . .. 0-06495 „ Vertical component .. .. .. .. .. 0-55516 ~ Total magnetic force .. .. .. .. .. 0-59828 ~

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Table of Hourly Values (Greenwich Mean Civil Time).

12

Magnetic Declination (east of north) : 16° -f tabular minutes. Day of Month. fe 0f Oh. lh. ! 2h. j 3h. 4h. 5h. j 6h. 7h. 8h. i 9h. j lOh. ! llh. : 12h. 13h. 14h. 15h. I 16h. i 17h. 18h. 19h. 20h. 21h. i 22h. 23h. Mean. 1918. January 1 .. " 2 3 5 6 7 8 9 ", 10 11 13 14 15 0 52-5 I 56-8 i 59-6 59-9 59-9 59-2 : 571 55-5 54-3 54-7 54-5 I 54-2 53-7 I 53-8 54-3 54-4 : 54-8 ! 53-6 51-4 49-3 46 8 45-6 47-9 51-1 54-U 1 54-3 j 58-2 j 59-4 59-8 | 59-1 58-7 | 56-7 55-5 55-4 54-8 54-6 54-3 54-3 i 54-2 . 54-2 54-3 ; 54-0 54-2 514 48-8 47-5 46-4 47-5 514 54-1 2 J 54-8 '■■ 58-8 : 59-9 59-8 ! 57-7 57-1 ! 55-9 ] 54-8 : 54-8 j 54-3 53-6 53-6 55-4 50-9 > 54-3 53-1 I 51-4 54-3 ■ 51-4 48-5 j 47-0 45-7 49-9 51-2 53-7 3 53-1 56-5 57-1 58-2 57-4 55-5 j 54-8 53-7 : 53-6 54-3 53-7 54-3 54-3 53-7 56-6 54-8 j 54-2 52-0 ; 50-8 49-8 \ 48-6 48-6 51-2 54-1 53-8 4 52-6 56-1 57-6 58-2 58-2 56-6 ; 54-8 53-7 52-9 | 52-3 53-1,52-0 53-5 52-1 | 53-0 51-9 544 54-3 54-8 50-5 j 48-5 48-6 49-9 52-4 53-4 ! ' ! i 5 55-6 58-8 61-1 61-2 | 60-5 58-7 56-6 55-8 52-7 52-6 52-0 53-7 54-2 53-7 56-1 53-6 54-5 54-2 50-1 48-1 ; 46-1 47-5 49-9,53-5 54-2 6 55-9 58-5 ; 59-9 j 60-3 59-1 56-3 54-4 53-7 53-9 \ 53-6 54-1 54-1 54-6 544 , 54-7 54-6 53-9 i 53-0 ; 52-0 49-9 ! 48-2 : 48-5 49-5 52-6 54-2 7 54-8 57-0 57-9 ! 58-1 57-1 55-9 i 54-2 : 54-3 - 53-7 53-1 53-1 53-7 53-9 53-7 ' 53-7 53-3 53-1 | 53-0 | 50-9 49-2 48-6 j 48-5 j 49-8 53-7 53-6 8 56-5 59-9 59-9 ' 59-1 58-2 56-5 j 54-8 54-3 54-3 54-4 ! 54-4 54-2 54-3 54-3 \ 54-3 54-2 53-1 I 53-0 i 50-9 50-3 49-8 i 50-3 514 55-8 54-6 9 I 58-8 j 62-7 62-7 614 60-5 58-1 55-9 54-8 54-2 55-4 54-3 54-2 54-3 51-9 | 51-7 51-7 52-0 ! 50-7 - 48-6 47-5 47-5 ! 47-0 49-4 53-5 54-1 10 j 55-9 59-3 61-1 61-1 59-9 58-2 55-5 53-7 531 53-7 53-6 53-1 55-3 53-7 53-7 53-1 531 52-6 50-9 | 48-6 48-1 48-3 51-4 56-5 54-3 11 58-8 61-7 62-7 62-1 59-3 57-4 55-4 54-3 53-7 54-3 1 53-7 53-9-49-1 48-1 48-6 52-0 52-0 49-6 47-6 47-2 47-4 454 47-0 49-2 52-9 12 54-8 58-2 61-5 62-1 59-9 ' 59-3 55-4 : 54-8 53-9 52-0 ! 53-5 54-3 ; 54-3 544 ' 58-8 56-6 54-2 j 53-0 ! 50-9 i 49-2 47-9 48-8 50-2 52-6 54-6 13 55-4 57-6 59-8 58-2 59-9 57-6 54-3 54-3 j 54-3 544 j 54-3 ; 54-3 ! 53-7 54-2 54-8 55-4 54-5 54-4 51-7 50-3 47-0 47-0 j 50-0 54-5 54-2 14 58-2 61-0 62-1 62-2 59-8 55-4 531 53-1 53-1 53-1 52-6 : 52-0 | 54-2 54-3 54-8 54-8 55-4 54-3 52-0 51-1 47-5 46-5 49-2 54-3 544 16 17 19 „ 20 15 54-8 61-0 62-1 ; 61-6 60-9 57-7 544 54-3 53-3 51-9 52-8 54-2 54-3 54-6 54-8 55-4 54-3 53-7 51-7 49-8 47-3 464 47-9 49-3 54-2 16 53-1 57-1 61-1 62-2 61-6 58-8 55-9 54-4 53-7 53-9 53-5 54-3 54-3 54-2 54-8 54-3 53-9 54-3 53-0 50-9 49-2 48-1 49-8 51-4 54-5 17 53- 1 57-0 60-5- 61-0 60-5 58-8 . 56-5 55-4 54-4 54-3 : 53-5 53-3 53-9 53-9 ; 53-8 j 54-1 ; 53-7 53-7 53-1 51-4 49-2 47-5 4-9-1 52-6 54-3 18 54-3 57-1 59-3 59-8 58-9 57-6 56-4 55-4 54-3 54-3 53-6 53-7 54-3 54-3 I 53-1 ] 53-1 i 53-1 53-1 j 52-6 50-3 49-9 49-0 49-3 52-0 54-1 19 54-8 57-6 60-0 61-0 60-9 59-9 58-2 56-6 56-4 55-9 ! 54-9 53-1 52-0 52-0 | 52-6 52-6 : 52-6 52-0 | 50-9 49-2 48-6 j 47-6 , 49-8 53-1 i 54-3 21 22 23 24 25 26 27 28 29 30 31 - • i " 20 56-5 59-9 62-3 \ 62-2 60-9 58-8 , 56-9 56-4 55-9 55-9 55-3 54-6 53-1 54-2 531 58-8 514 52-2 j 53-1 50-8 ! 50-3 49-8 50-3 52-6 ; 55-2 21 55-6 56-5 58-9 I 58-7 57-6 56-6 ! 55-5 55-9 55-9 55-5 54-3 54-3 53-7 54-8 j 53-1 53-0 < 53-1 52-1 ! 50-9 49-2 ! 49-2 49-6 53-1 56-5 54-3 22 57-8 58-8 59-3 59-3 J 58-2 56-5 54-4 54-2 54-3 154-3 54-3 54-2 54-3 53-7 53-1 53-1(53-1 52-6 51-0 . 48-6 47-5 46-3 48-5 510 53-7 23 54-3 59-3 59-9 '' 59-9 58-2 i 56-5 ' 54-3 54-3 54-8 | 55-4 54-8 54-8 53-7 53-1 53-1 51-0 : 50-8 50-9 j 52-0 49-9 ! 50-8 50-1 51-4 54-8 54-1 24 57-1 59-3 61-0 60-0 58-9 56-5 i 54-4 54-3 ! 54-3 i 54-3 53-7 i 54-2 55-5 54-7 54-3 54-2 53-1 53-1 ' 514 49-5 j 48-1 47-0 48-5 52-6 54-2 25 55-9 58-8 61-0 60-5 58 2 56-4 54-6 54-3 53-7 53-7 54-3 54-3 54-3 54-3 54-3 54-3 53-7 52-7 514 50-9 -18-8 48-8 50-3 53-7 54-7 26 58-4 62-7 63-3 63;3 61-1 58-9 56-5 j 54-8 53-9 54-3 53-0 53-1 53-1 510 53-5 . 53-8 531 52-9 50-9 49-6 48-8 48-1 51-4 531 54-7 27 544 57-0 58-8 58-8 58-2 55-9 54-3 | 53-3 53-3 i 54-2 54-2 54-3 54-3 54-3 51-3 54-2 53-7 54-3 514 ; 49-6 49-9 49-8 52-0 54-6 54-1 28 57-6 60-0 60-7 60-0 58-8 57-5 56-6 564 56-5 54-2 54-4 54-3 54-3 54-8 53-7 52-1 54-3 51-0 50-9 51-4 51-2 48-8 52-6 554 54-9 29 56-2 58-2 57-3 57-1 57-5 56-5 55-9 55-4 53-7 49-8 48-1 49-2 53-5 49-8 50-5 ■ 50-8 j 49-0 52-6 52-6 49-8 49-6 50-9 53-7 52-6 52-9 30 57-5 59-3 58-8 57-7 56-5 554 54-8 54-8 54-8 52-3 ! 48-8 51-9 54-3 56-2 49-5 49-8- 53-0 51-9 57-1 54-3 531 52-0 52-7 57-1 54-3 : i - ! ■ U < • I ' ! . _ - . . - Means .. 55-6 58-7 60-2 60-2 59-1 57-4 55-4 54-7 54-3 53-9 53-5 53-7 53-9 53-5,53-7 53-6 53-3 52-9 51-6 49-8 48-6 48-1 50-1 53-2 54-1 i

C— 1a

13

Table of Hourly Values (Greenwich Mean Civil Time)- continued.

Magnetic Horizontal Force . 0-22000 C.G.S. + tabular y. Day of Month. of l Oh. ! lh. ! 2h. ' 3h. I 4h. Day. j | j 5h. 6h. ' 7h. Sh. 9h. lOh. i llh. ; 12h. 13h. 14h. 15h. 16h. 17h. 18h. 19h. 20h. 21h. 22h. 23h. Mean. 1918. January 1 2 3 4 5 0 296 312 333 356 365 363 | 339 337 : 347 350 350 349 347 344 341 344 344 346 351 348 344 324 311 309 340 1 313 326 332 i 348 ( 352 358 j 357 358 ! 355 356 356 356 355 351 347 346 350 350 352 345 338 318 306 308 343 2 311 318 328 342 '< 350 347 348 , 352 ! 362 277 359 362 377 355 354 360 345 355 360 349 345 328 323 318 347 3 319 329 336 343 372 347 342 341 344 353 356 351 350 345 352 347 336 340 340 325 322 308 302 306 338 4 317 313 337 339 351 352 347 345 346 346 339 345 358 334 336 332 337 332 340 327 313 299 287 290 332 .. .._ -- 6 7 8 9 10 5 307 320 332 334 325 342 351 346 342 337 332 • 338 337 339 364 342 : 329 337 328 318 302 288 288 290 328 6 290 > 315 334 338 354 350 342 342 342 342 344 i 342 337 336 338 333 334 334 329 327 317 305 303 308 331 .. . 7 ! 316 330 345 356 358 353 349 347 346 341 339 ! 336 , 331 335 332 333 334 332 331 328 318 305 302 308 334 8 312 321 339 353 357 260 357 f 53 346 345 347 j 343 334 341 342 339 340 340 339 325 313 308 301 308 332 9 332 351 358 359 360 358 358 368 354 351 343 345 340 333 339 334 341 339 336 322 316 301 297 , 296 339 11 12 13 14 15 10 314 329 342 348 355 344 347 346 343 340 348 339 346 336 333 335 335 335 333 326 318 306 301 304 333 11 315 320 330 344 354 365 354 359 355 356 360 352 351 324 331 341 314 346 329 316 304 294 297 278 333 12 293 318 330 333 334 332 -330 325 330 ■ 327 338 j 330 333 336 363 338 338 338 330 324 : 313 285 277 287 324 13 285 | 275 j 300 334 322 327 335 336 336 j 340 337 i 339 339 325 331 331 328 332 332 323 316 285 279 285 320 14 292 305 : 322 339 361 365 361 344 339 j 338 337 338 334 332 329 332 342 332 334 322 325 < 315 293 291 I 330 ,, 16 17 18 19 20 „ 21 22 23 „ 24 „ 25 ,, 26 .. 27 ,, 28 „ 29 30 .. i 15 296 287 304 313 328 335 340 338 340 339 342 340 337 335 333 333 318 333 335 333 322 303 295 287 324 16 281 288 305 322 339 344 369 371 343 ; 342 345 343 337 339 341 332 332 332 337 333 327 328 302 291 330 17 282 | 290 312 334 346 354 341 347 347 j 349 347 344 340 338 333 335 338 338 342 337 324 314 304 280 330 18 295 ; 302 317 335 348 355 358 356 353 I 355 352 347 348 344 339 339 1341 343 344 338 330 318 313 310 337 19 317 313 329 334 353 360 359 334 355 349 350 364 347 345 333 333 ! 333 333 328 328 326 318 315 315 336 ..20 332 328 333 351 362 358 351 348 340 354 362 354 351 342 344 360 346 327 335 330 323 311 305 297 340 21 317 327 330 334 336 348 349 339 340 343 344 338 339 336 330 329 334 334 334 329 324 312 312 319 332 ..22 327 330 332 341 342 347 348 349 342 342 340 339 337 336 335 335 335 337 ! 337 336 329 314 301 298 334 23 302 315 325 335 344 355 350 349 : 353 j 354 360 351 j 344 339 331 336 : 336 337 332 322 311 304 302 305 333 ..24 309 315 318 323 343 348 342 340 343 ! 340 j 338 ( 345 ' 340 333 I 331 331 331 335 336 333 326 313 302 297 329 25 308 318 333 350 347 340 334 341 337 342 344 340 ! 339 344 335 337 337 336 335 325 314 298 294 303 330 26 313 321 338 j 341 344 336 338 333 328 331 | 329 337 335 346 333 325 325 327 328 323 320 307 299 302 327 27 306 309 314 304 336 337 340 340 340 342 342 344 333 334 334 342 311 339 340 331 323 308 311 317 329 .. 28:325 337 341 349 357 348 360 359 352 364 366 346 347 355 358 339 358 349 343 337 317 297 290 311 342 29 315 310 318 315 319 319 323 320 344 329 | 308 315 342 325 318 337 345 335 318 304 291 215 232 227 309 „ 31 Means ..30 210 1257 252(262 289 308 310 328 331 327 330 342 320 339 339 317 315 325 332 327 300 302 279 273 306 .. 306 314 326 336 342 344 345 344 345 342 345 344 312 339 339 337 336 337 336 326 320 304 298 297 331 I ! i l.i

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14

Table of Hourly Values (Greenwich Mean Civil Time)— continued.

Magnetic Declination (east of north) : 16° -j- tabular minutes. Day of Month. *?- 0f Oh. lh. Day. | 2h. 3h. 4h. 5h. j 6h. 7h. j 8h. 9h. j lOh. llh. 12h. 13h. 14h. i 15h. 16h. 17h. I 18h. I 19h. j 20h. , 21h. I 22h. I 23h. Mean. i I I I I i ■ 1918. February 1 2 3 4 „ 7 9 10 11 12 13 14 15 16 17 1.8 19 - 31 ! 57-6 58-2 59-3 57-6 ( 57-1 | 55-9 55-4 54-3 j 53-1 | 53-3 I 53-1 \ 53-0 53-7 54-3 54-6 55-3 54-8 54-3 54-8 53-5 50-9 50-0 52-0 53-1 I 54-6 32 ; 53-5 55-4 57-1 57-6 55-9 '' 56-5 55-9 55-4 ! 54-8 54-3 53-1 : 53-7 53-7 544 54-3 ■ 54-4 , 53-3 53-0 54-2 51-4 50-1 49-8 50-9 51-4 53-9 33 53-3 j 58-2 61-0 61-1 ! 59-8 \ 57-6 56-6 55-9 55-4 I 53-9 j 53-0 j 54-3 54-3 54-3 53-1 '. 54-3 54-3 53-6 52-6 51-0 50-2 49-2 50-9 52-1 , 54-6 34 53-1 56-5 58-8 ' 58-8 ! 58-2 57-1 55-5 55-3 54-8 55-4 1 54-8 | 54-3 54-3 54-3 54-3 - 53-7 54-2 54-8 52-2 50-9 49-6 48-8 51-4 52-6 54-3 I ! • 35 53-9 : 57-1 57-6 56-5 ! 56-5 55-9 ; 55-3 54-5 55-1 ( 55-4 \ 53-5 I 50-3 48-6 49-2 52-1 j 51-8 i 52-6 - 53-7 52-0 i 49-8 48-6 47-4 49-2 51-4 52-8 36 ; 53-1 ! 54-8 57-6 58-2 62-2 61-0 ! 60-5 . 58-9 56-5 554 | 55-4 54-9 | 54-8 53-3 53-1 ! 514 52-0 ! 52-0 53-1 ! 52-6 | 52-0 514 53-7 54-8 : 55-1 37 57-1 58-2 57-6 58-2 57-7 57-0 ' 56-5 56-4 54-3 55-9 55-4 53-3 53-7 ' 53-7 j 54-1 53-1 53-1 : 53-1 52-0! 49-9 49-2 49-2 50-9 52-6 54-3 38 53-8 56-9 57-6 55-9 54-8 54-8 j 54-4 54-5 54-4 54-8 54-8 54-4 54-3 54-4 53-7 53-1 52-6 ' 52-6 51-8 50-9 ' 50-3 50-9 53-1 55-9 53-9 39 57-6 59-9 58-7 56-6 56-5 56-5 | 55-9 55-9 , 55-8 55-9 55-4 56-6 54-3 54-4 54-3 54-2 53-7 : 53-4 52-0 : 50-9 j 47-6 49-2 53-1 58-2 54-9 40 58-9 61-0 ' 61-6 ; 58-8 57-5 55-9 54-3 ( 54-8 52-6 53-3 54-3 j 54-4 54-1 - 54-3 53-7 53-3 52-6 54-3 52-6 49-8 49-8 49-8 I 52-1 55-9 54-6 41 58-8 62-2 •■ 61-1 59-3 57-6 55-9 54-2 54-3 54-3 514 53-7 ; 54-3 54-3 i 55-3 54-2 55-7 ( 54-4 ■ 53-4 52-6 47-5 50-3 49-3 i 51-0 53-1 54-5 42 53-9 ; 55-9 59-2 59-9 54-8 56-4 54-3 j 54-4 52-1 530 60-5 57-1 48-8 49-8 53-7 54-3 ; 52-0 52-0 55-5 55-9 56-5 53-7 j 52-0 53-4 54-6 43 54-3 ! 55-8 58-7 59-1 57-6 55-9 ( 56-5 ( 54-8 i 48-6 52-1 50-3 50-9 52-6 53-3 52-5 52-7 I 53-1 ! 53-1 54-2 50-9 50-2 47-5 j 50-9 52-1 53-2 44 56-2 ! 59-9 61-6 61-6 58-8 58-8 57-6 i 56-4 54-3 54-3 55-1 52-0 54-3 544 55-4 54-3 54-3 | 54-2 52-6 49-9 50-1 47-5 49-8 52-0 54-8 45 56-2 60-5 ' 62-6 61-6 59-9 | 57-6 55-2 55-9 ' 55-7 55-4 ; 54-3 53-7 54-6 53-3 54-8 53-3 57-6 60-1 53-7 49-8 i 48-6 41-9 45-8 50-6 54-8 46 53-7 57-1 60-9 62-5 61-0 59-3 57-7 57-1 I 54-8 53-3 54-2 52-8 j 514 53-1 53-7 54-3 54-3 ! 54-1 53-1 51-7 49-8 49-8 49-9 51-4 54-6 47 53-7 56-9 59-3 60-3 '' 60-5 60-0 j 58-8 56-5 55-9 55-9 54-4 54-3 54-2 54-2 54-3 53-1 53-1 53-5 53-1 50-9 ! 48-1 48-1 48-6 51-9 54-6 48 53-6 55-5 57-1 58-2 58-8 58-1 | 57-5 56-5 i 54-3 55-8 55-3 55-2 54-3 54-3 53-1 53-1 ; 53-0 j 53-0 52-61 50-9 < 49-5 48-1 49-8 51-9 54-6 49 53-0 54-9 56-7 57-5 58-3 58-8 ; 58-0 56-5 j 554 55-5(55-1 54-8 54-3 54-3 54-3 54-2 53-7 53-7 52-6 51-4 49-9 49-2 51-2 53-8 54-4 50 55-7 56-7 l 56-9 : 571 56-3 ; 55-4 j 55-9 j 56-5 56-4 56-5 : 55-9 I 55-4 54-3 j 54-3 53-8 53-7 : 53-1 54-3 ! 53-9 ( 51-8 49-9 48-6 51-9 55-9 54-6 51 58-0 58-8 59-3 j 58-8 59-0 58-8 57-1 ( 57-6 56-5 55-9 53-0 54-4 54-8 ; 55-1 54-4 ( 54-2 I 53-7 53-1 ' 52-0 ( 51-0 ; 49-9 49-8 514 54-8 551 52 57-3 I 59-0 j 59-9 58-9 57-5 55-8 54-8 ': 55-4 : 54-7 55-4 j 54-7 l 54-8 | 54-7 I 54-7 54-2 54-2 54-3 53-7 534 51-6 ■ 50-3 < 48-9 49-1 52-0 54-6 53 54-3(57-7 59-9 59-9 58-0 57-1 56-5(55-4 54-5 53-7 53-9 54-3 ; 54-3 ] 54-3 53-9 52-3 53-1 51-6 49-8 50-9 48-6 48-6 49-9 53-3 54-0 54 56-5 58-9 59-9 58-8 58-3 j 56-5 54-3 j 54-3 54-4 52-7-53-1 54-3 53-7 52-7 53-5 54-3 54-1 53-1 ( 52-0 50-3 ' 48-1 47-5 49-0 514 53-8 55 .53-7 57-1 57-6 57-6 57-5 56-5 56-4 56-5 55-5 554 54-8 54-3 54-3 54-3 54:3 54-3 53-7 54-2 53-1 51-4 49-2 47-5 49-2 ! 53-1 54-2 56 56-3 59-4 61-0 59-9 58-7 56-5 54-8 55-1 I 54-8 54-8 ( 52-6 53-9 ! 54-3 ; 54-4 54-3 '■■ 54-3 54-4 54-6 54-3 52-6 i 50-3 48-6 49-4 I 53-4 54-7 57 57-6 60-0 61-0 60-9 59-0 55-5 55-9 55-9 \ 55-4 55-4 ( 54-8 54-3 ' 54-4 ; 54-3 54-3 54-2 53-7 53-1 51-4 49-8 ! 45-8 45-6 45-8 I 50-9 54-1 58 53-7 57-1 61-6 60-2 60-7 58-8 54-8 j 55-4 \ 51-4 1 51-4 50-6 52-0 52-0 52-0 47-5 48-8 i 52-0 53-3 52-1 49-9 51-4 52-1 49-9 52-1 53-4 ; : - ! : i i .. 55-3 57-8 59-3 | 59-0 58-2 57-1 56-1 : 55-7 \ 54-5 54-5 54-3 54-0 53-6 53-7 53-7 53-6 53-6 53-7 52-8 51-0 49-8 48-9 | 50-4 53-0 54-3 20 21 22 23 24 25 26 27 28 Means 58-2 57-1

15

(~—- 1a

Table of Hourly Values (Greenwich Mean Civil Time)— continued.

Magnetic Horizontal Force : 0-22000 C.G.S. + tabular y. Day of Month. fe- of Oh. lh. Day. 2h. : 3h. 4k 5h. 6h. ! 7h. , 8h. 9h. lOh. | llh. I 12h. | 13h. 14h. j loll. I 16h. I : : ! i i i i 1 > 17h. 18h. i 19h. j 20h. j 21h. j 22h. 23h. Mean. : i j I L 1918, February 1 2 4 5 6 7 8 .. . 9 10 „ . 11 12 13 14 15 16 17 18 19 20 21 22 23 24 „ 25 26 27 28 Means • • I 31 284 ! 300 283 295 316 307 319 311 317 - 326 311 326 320 ( 318 ! 316 ! 314 i 314 - 306 I 315 ! 304 302 : 265 299 293 j 307 32' 292 290 299 298 - 324 334 | 340 367 335 [ 333 337 332 326 332 ( 326 : 331 ; 332 ( 327 312 305 301 291 ! 286 286 ( 318 33 302 295 329 317 , 333 335 336 334 '. 335 : 331 331 329 331 341 '■ 331 ! 324 324 ! 329 329 324 321 - 314 307 '< 304 - 324 34 303 302 305 315 | 325 333 336 , 341 ' 341 342 341 340 339 336 ' 334 i 336 336 ( 334 331 331 326 321 316 315 ; 328 35 316 : 321 322 326 : 326 - 334 - 336 : 392 378 ( 353 362 349 326 323 I 324 324 I 324 j 328 : 324 319 316 309 314 311 332 36 317 ' 301 \ 302 296 ! 296 336 313 325 ( 320 319 I 309 318 ; 313 322 334 314 317 j 321 ( 314 j 305 I 299 , 299 : 307 310 ; 313 37 313 : 315 318 306 315 310 325 ; 337 ! 315 I 322 ' 327 338 ! 333 333 333 315 318 318 ( 315 ! '308 : 306 296 296 297 ( 317 38 307 i 316 319 322 321 ' 324 326 j 331 [ 334 ! 331 j 332 I 331 ! 326 329 329 326 324 i 324 ' 324 I 316 : 309 298 297 , 300 ( 321 39 316 326 ( 309 338 348 345 346 343 : 346 349 I 347 345 j 345 j 343 337 ( 336 336 ( 335 333 j 328 : 310 278 294 ; 294 . 330 40 317 : 338 326 324 321 332 333 324 j 321 ( 315 319 ! 334 ( 334 334 334 337 334 j 329 " 322 319 \ 309 292 ; 270 282 321 41 301 311 323 340 323 325 327 , 318 > 327 ' 333 I 338 338 333 355 337 323 327 j 330 323 313 ' 286 257 ; 257 284 318 42 273 j 285 ; 292 290 322 312 ( 290 ! 307 ' 300 307 - 317 321 \ 322 334 297 327 334 j 331 ' 315 266 288 256 241 214 298 43 220 I 250 I 259 268 272 284 ' 289 | 287 311 292 ( 292 294 j 229 ; 295 306 299 305 i 311 301 306 289 : 273 263 255 281 44 253 ' 256 257 282 300 305 ; 293 295 290 303 ( 290 302 | 301 303 303 j 310 I 312 317 318 ! 315 301 ; 292 282 278 ; 294 45 272 276 j 291 300 312 | 315 ! 320 309 337 i 337 I 323 329 ; 323 318 323 \ 325 ! 338 339 : 345 ! 342 324 323 290 274 j 316 46 j 276 276 291 289 310 i 323 ! 332 334 325 323 ( 315 325 362 j 325 \ 308 310 313 315 318 ' 318 ! 308 : 286 ! 281 ! 274 ( 310 47 ; 275 : 282 287 299 316 326 330 329 319 324 329 338 323 319 I 325 319 316 319 ! 319 318 ! 311 i 299 ( 297 ! 293 ; 313 48 298 298 ., 308 322 327 ; 325 333 332 337 ! 331 332 330 325 327 ( 326 321 324 j 323 ! 321 ! 316 \ 311 299 295 299 319 49 306 306 310 310 333 341 I 335 331 339 : 337 333 331 : 319 ; 325 ( 325 325 328 328 \ 326 ( 320 315 ; 306 305 306 323 I I I 50 302 I 305 ; 313 319 327 329 ! 334 ; 334 340 j 344 > 344 341 332 334 ! 334 334 334 332 336 324 309 300 290 290 324 51 ! 306 i 306 : 318 329 329 320 ( 286 333 330 I 335 ( 328 316 315 318 ; 320 319 319 ! 316 317 312 j 305 i 295 288 288 315 52 ; 291 301 313 ! 318 326 331 333 326 328 l 331 j 331 333 I 332 332 ' 331 327 328 j 327 327 322 ( 316 | 307 300 295 321 53 ( 298 310 I 315 320 328 329 j 323 330 328 i 333 ( 333 333 328 ; 332 ( 328 337 342 j 337 330 323 323 308 ( 286 281 322 54 ( 292 302 312 ; 309 312 309 307 316 310 | 309 | 316 316 j 336 ( 314 | 309 309 . 309 ' 309 312 309 : 301 289 277 272 306 55 j 281 295 | 313 > 322 322 325 j 324 327 329 i 332 329 ! 329 - : 321 I 322 ! 324' 325 326 326 326 326 321 309 \ 301 301 319 56 ! 315 327 i 335 : 344 346 336 ''■ 327 333 333 ; 338 335 : 335 I 333 j 331 331 330 l 330 , 334 335 335 325 313 305 308 330 57 317 ( 326 334 ! 341 343 ( 342 ; 340 340 340 342 341 I 340 | 340 ! 338 339 339 337 i 339 331 328 317 318 313 318 333 58 i 317 | 320 | 332 322 333 ; 321 I 292 309 292 I 283 318 I 330 | 328 ( 361 324 319 327 I 324 i 326 \ 326 ( 284 301 . 301 ( 394 326 .. 295 i 301 308 i 313 322 325 322 j 328 : 327 327 327 i 329 I 325 i 328 i 325 ■ 323 325 i 325 323 317 308 296 291 | 290 317 I.I.I | i ; ! j :

C— U.

Table of Hourly Values (Greenwich Mean Civil Time)— continued.

16

Magnetic Declination (east of north) : 16° -J- tabular minutes. Day of Month. of ( Oh. I lh. 2h. I Day. i 3h. 4h. \ 5h. ' 6h. j i 1 I 7h. 8h. ( 9h. ; lOh. ; llh. 12h. 13h. I 14h. | 15b. j 16h. 17h. 18h. ( 19h. 20h. 21h. '. 22b. 23h. Mean 1918. March 1 2 » 3 4 •j -5 7 „ 8 "„ 10 „ 11 „ 12 „ 13 ,. 14 „ 15 ,; i6 -, 17 ,, 18 „ ' 19 .. 20 „ 21 „-. 22 „ 23 „ 24 .. 25 :, 26 r .. 27 ., 28 „ 29 ,, 30 ., 31 Means j 59 53-7 55-4 58-3 59-3 ' 59-8 j 58-5 : 56-6 554, 54-8 54-8 53-0 53-0(53-7 53-7:54-8 54-3 54-7 : 54-4 53-7 52-0 j 49-8 47-5 48-1 50-3 54-2 60 54-3 57-3 I 59-3 60-5 | 58-8 57-7 57-1 55-9 55-4 ( 54-8 52-0 531 ; 54-3 54-4 54-4 54-3 54-3 I 56-5 54-3 52-0 49-8 48-1 49-2 52-5 54-6 61 56-9 60-5 61-1 60-5 59-3 57-6 55-9 55-7 55-1 53-5 49-2 50-0 474 49-8 52-6 50-8 53-0 j 52-0 53-7 50-9 48-1 47-0 49-2 52-6 53-5 .. I 62 56-5 i 59-8 61-0 59-9 58-2 55-5 54-3 54-8 ! 55-8 53-7 53-1 53-7 | 54-3 j 54-3 54-3 : 54-6 . 54-4 | 54-3 54-3 53-1 50-3 48-8 49-8 52-0 54-5 .. 63 54-7 57-6 59-3 59-9 58-2 56-5 | 55-3 54-8 ( 54-4 54-3 53-7 53-3 ; 54-6 54-8 54-8 54-3 i 54-3 ( 54-3 54-2 52-0 50-3 48-1 | 49-8 52-0 54-4 .. i 64 54-8 57-6 60-0 59-9 59-3 58-2 ( 56-4 54-8 ( 55-4 '■ 55-9 55-4 54-8 55-4 54-3 53-7 53-9 54-3 54-3 53-7 52-0 50-3 49-3 \ 49-9 52-3 i 54-9 .. I 65 54-8 56-8 58-8 59-8 59-9 58-8 : 58-2 56-9 ", 56-4 55-9 55-4 55-1 54-3 54-3 54-3 54-3 54-3 54-2 53-7 : 52-0 50-8 49-6 I 47-0 53-7 55-0 .. I 66 54-8 56-5 67-9 76-8 ( 72-8 66-1 ; 62-1 61-0 ( 58-8 58-2 55-9 53-1 j 55-4 ( 55-3 54-8 55-4 54-3 54-8 57-6 54-3 52-0 49-2 ' 52-0 52-7 ! 58-0 67 55-9 58-8 60-5 59-9 1 59-3 57-6 564 554(54-8 55-2 55-3 54-8 554 554 54-8 554 55-2 544 54-3 53-1 514 49-9 51-7 53-5 j 55-1 68 55-9 ( 58-2 : 59-9 59-3 j 58-2 ! 56-5 '•■ 55-9 55-5 ( 55-4 55-2 55-4 55-4 55-4 | 55-4 55-4 54-8 58-2 55-4 52-5 : 52-6 50-3 49-8 '■■ 50-3 53-7 ; 55-2 69 57-3 ! 60-5 62-2 62-2 59-9 ; 58-8 56-5 56-5 ( 55-9 ■ 55-9 54-8 54-4 54-8 : 54-8 54-8 ' 57-0 55-4 52-0 55-9 ( 54-6 51-4 52-0 52-1 52-6 | 56-0 70 55-1 ; 57-9 60-1 60-5 59-8 57-6 53-0 53-1 - 53-1 ( 51-9 47-0 52-3 52-0 54-4 52-0 53-7 56-5 55-5 55-2 53-1 49-2 48-6 47-5 49-8 53-7 71 53-6 56-6 58-8 60-5 60-1 57-6 55-3 55-4 54-2 ! 54-4 54-8 54-8 55-2 55-3 ! 55-4 54-8 54-3 54-4 54-3 ; 52-6 49-2 47-0 47-0 ■■ 49-8 54-4 72 53-9 57-1 62-7 63-9 61-1 58-4 564 55-9 554 53-3 > 53-7 54-3 544 544 54-3 54-3 55-9 57-6 564 53-7 49-8 47-6 48-1 50-1 55-1 .73 55-1 59-9 61-6 62-2 j 62-1 58-9 58-2(58-8 57-6 56-6 554 54-8 54-3 544 152-6 51-0 53-1 54-2 52-0 | 50-3 j 50-3 44-8 49-8 52-0 55-0 74 53-1 57-6 60-2 63-3 62-7 61-0 58-7 58-2 55-3 55-5 55-4 54-8 53-1 58-2 50-9 49-8 54-2 51-0 55-3(53-1 53-3 514 50-9 51-9 55-4 75 54-2 57-6 59-8 58-2 59-9 58-7:57-1 56-5 56-5 55-9 55-5 55-4 54-8 544 54-3 54-8 54-8 54-8 54-4 53-7 52-0 50-9 511 52-6 55-3 76 544 i 57-1 ! 58-9 60-0 59-1 57-6 j 57-5 57-5 56-5 56-6 , 55-3 510 55-9 : 53-5 ( 53-7 54-4 54-8 55-1 54-3 53-0 ! 51-2 49-2 .49-6 , 51-4 ( 54-9 .. I 77 54-8 : 58-8 i 59-9 i 59-9 ( 58-9 57-1 : 56-2 56-5 55-9 55-5 55-4 53-1 53-7 : 53-7 ! 53-4 54-5 54-3 54-2 53-7 53-0 ( 49-2 48-3 49-2 : 51-9 I 54-6 .. j 78 59-7 I 57-6 : 59-3 ; 60-2 59-9 58-2 j 57-1 57-0 ( 56-9 57 1 54-3 44-7 52-0 53-0 ( 52-0 53-7 54-1 54-2 53-7 ; 52-6 50-5 48-8 49-9 514 ( 54-5 .. ( 79 54-3 57-0 58-9 59-9 59-3 58-2 ( 57-0 57-2 \ 57-1 55-9 56-5 55-9 54-4 : 50-3 50-1. 52-0 53-7 53-5 54-3 ( 53-7 51-0 49-2 49-5 51-4 ( 54-6 .. ! 80 55-4 58-8 60-9 60-5 59-9 58-3 ' 55-9 56-5 55-4 55-3 54-4 53-7 50-9 51-9 53-1 52-6 52-6 56-6 54-3 50-3 49-2 49-2 49-9 52-6 j 54-8 81 55-9 58-9 60-9 61-6 61-6 I 57-1 ( 56-5 56-5 i 55-6 55-5 52-6 53-7 53-1 54-2 55-3 55-1 554 54-3 55-6 55-2 54-8 51-7 . 49-9 \ 50-8 55-5 82 54-5 57-6 59-9 60-5 59-3 ! 57-6 ! 57-1 , 57-1 55-4 ' 52-3 53-7 54-8 54-9 55-4 1 55-4 ; 55-3 55-2 54-8 54-4 : 53-3 514 49-8 50-3 52-6 55-1 83 55-5 59-3 ' 60-9 60-5 58-8 ' 57-1 ! 55-4 55-9 554 55-4 55-4 55-1 54-8 55-3 | 55-2 i 55-4 ' 55-4 ! 55-3 54-5 ( 53-1 51-9 50-3 50-1 ; 51-9 55-4 .. ( 84 54-4 , 57-1 59-0 59-3 58-2 ; 57-0 ( 55-9 56-5 ( 55-4 55-5 52-3 51-4 53-1 54-3 54-9 54-8 56-5 j 55-9 54-3 ; 53-3 51-4 49-8 50-8 \ 53-3 54-8 .. ! 85 58-2 60-5 j 61-6 60-5 I 58-8 57-0 55-5 54-8 53-7 53-0 \ 52-0 52-6 i 53-0 54-3 53-9 53-1 55-4 55-9 54-3 54-3 52-6 51-4 50-8 53-5 55-0 86 55-5 | 58-8 : 60-1 ! 59 9 57-6 ! 55-9 ( 54-8 54-3 j 54-8 ( 54-8 j 54-3 54-3 54-3 54-4 54-3 52-6 54-2 ( 53-7 53-9 53-5 53-1 52-6 52-6 ! 53-7 54-9 87 56-5 59-8 i 60-9 ; 59-9 58-8 57-6 ( 56-5 55-4 ! 54-4 ; 52-6 544 54-4 , 54-3 54-6 54-9 , 54-3 54-2 ! 54-8 . 54-9 54-8 52-3 50-9 51-0 53-5 54-5 88 56-5 58-7 : 59-9 j 59-9 58-8 57-1 55-9 554 j 52-8 | 54-2 : "54-3 54-3 54-8 54-8 554 i 54-3 j 55-9 ! 54-8 54-3 53-1 52-6 50-3 50-8:51-6 55-0 89 ; 54-8 57-3 58-9 59-3 58-8 57-6 56-6 56-5 55-9 55-5 54-3 54-4 54-3 1 52-1 - 52-6 54-8 ( 54-3 , 54-4 54-3 53-7 53-1 ( 50-9 50-3 ! 50-9 54-8 .. j .. 55-3 58-2 60-4 61-6 59-9 I 58-0 '. 56-5 56-2 55-5 55-0 54-0 53-6 53-9 54-2 53-9 54-0 ( 54-7 ' 54-6 54-4 53-0 ! 51-1 ( 49-3 49-9! 52-1 54-9 54-9 i

17

C—la

Table of Hourly Values (Greenwich Mean Civil Time)— continued.

3—C. 1a

Magnetic Horizontal Force : 0-22000 C.G.S. + tabular y. Day of Month. !No. of I „, ,. t-. - Oh. In. 2h. 3h. 4h. 5h. 6h. 7h. Sh. i 9h. [ lOh. llh. ' I2h. 13h. Uh. 15h. ii.ih. 17h. I 18h. . I . 19h. 20h. 21h. 22h. 23h. Mean. I I 1 I I i l-l 1918. ilarch 1 59 : 285 290 290 298 317 319 332 322 324 j 321 339 322 322 315 319 320 321 323 324 321 316 304 291 284 . 313 0 ! ., 3 4 5 6 7 ■ „ 8 ,, 9 ., 10 ,, 11 ., 12 „ 13 ,, I* „ 15 „ 16 ., 17 „ 18 ., 19 ,, 20 „ 21 ,, 22 , 23 ,, 24 ., 25 ,, 26 „ 27 .., 28 „ 29 „ 30 „ 31 Means 60 231 j 309 312 i 327 329 329 , 329 327 331 j 336 332 328 324 327 - 327 329 329 331 334 \ 329 , 309 299 287 279 320 61 283 I 287 297 : 316 327 326 313 324 320 j 319 322 346 300 322 I 317 324 329 316 312 314 309 302 278 268 311 62 274 290 I 308 325 323 322 323 329 328 ( 328 328 328 320 318 | 320 320 323 321 323 320 311 301 I 291 286 315 63 290 295 303 311 321 326 327 329 336 ! 338 338 338 328 329 ; 326 326 325 326 328 : 326 319 305 [ 299 294 320 64 298 305 312 322 ( 332 330 332 325 327 j 330 339 339 339 330 332 331 328 330 332 330 325 317 310 308 325 65 315 323 318 321 323 333 j 336 336 336 I 333 333 : 333 328 328 j 326 328 328 330 333 332 323 321 : 333 316 ( 328 66 : 307 | 270 212 j 212 261 274 j 257 247 255 ! 258 264 281 273 265 ' 263 264 266 , 267 258 ( 262 265 265 261 256 261 67 254 257 269 283 291 293 ! 293 293 310 305 305 306 326 301 ( 300 300 301 301 302 , 301 294 283 277 270 : 292 68 274 276 : 283 298 300 305 ( 305 305 307 307 310 310 310 310 310 330 322 322 307 300 291 278 266 j 276 300 69 265 289 294 291 305 316 ! 304 307 318 323 323 326 326 321 321 333 323 321 308 : 298 307 296 279 277 307 70 273 263 270 : 293 300 320 i 273 266 278 I 293 307 ! 283 293 288 310 315 300 305 305 298 273 2-76 274 262 288 71 238 262 286 299 : 309 306 ( 304 305 311 314 315 314 314 309 316 311 314 316 314 316 306 294 '. 277 > 267 301 72 ; 264 , 280 290 304 314 321 319 321 322 ': 323 319 324 326 324 319 314 314 318 329 328 319 299 : 280 ! 265 310 73 261 273 249 . 319 342 352 347 ! 329 324 334 325 328 320 319 322 320 310 : 312 .344 i 334 310 298 290 i 282 314 74 279 296 289 308 299 307 306 | 318 316 | 322 317 319 322 386 336 309 361 317 . 293 312 318 271 264 254 309 75 ; 262 272 278 , 288 ; 295 307 310 314 314 311 314 313 311 310 309 309 309 309 314 310 307 292 282 287 309 76 291 : 294 300 i 306 : 317 329 322 322 323 323 322 315 325 : 301 305 308 309 310 310 306 298 290 285 281 308 77 278 ; 286 I 297 ( 305 ( 314 316 319 : 319 321 324 320 320 i 320 : 325 : 313 312 317 , 317 315 313 : 308 j 304 299 299 311 78 295 i 298 i 302 j 312 ! 322 327 328 ( 326 : 331 329 333 335 ' 322 \ 318 | 318 315 313 ! 312 ] 315 312 ( 305 I 300 295 298 \ 315 79 307 , 311 ( 315 319 319 323 323 : 324 323 325 ( 325 325 , 317 ; 312 ( 318 317 314 313 307 305 293 : 288 276 280 312 80 274 278 277 , 298 309 314 304 318 318 . 321 322 320 325 347 312 338 319 294 314 314 306 ( 294 279 274 307 81 : 270 278 286 ' 281 302 304 320 319 i 320 ( 325 324 320 324 316 317 319 320 320 320 319 302 302 290 278 307 82 272 273 282 i 299 306 303 306 306 302 321 ' 310 316 314 319 ! 314 344 314 314 314 311 310 307 287 279 304 83 ; 282 288 299 ■ 308 317 319 314 319 319 324 | 323 327 322 321 ( 321 321 321 j 321 I 321 320 318 299 287 284 312 84 i 287 294 302 j 313 322 329 331 335 329 327 j 327 325 320 315 ' 317 ; 323 333 [ 329 328 324 319 319 285 276 ; 313 85 ! 288 293 301 ( 310 322 '. 315 : 312 305 305 319 310 310 310 309 , 325 : 310 310 I 315 327 ; 330 315 288 I 288 283 : 308 86 288 294 303 313 314 315 '. 315 312 318 322 322 322 325 334 i 329 j 321 319 I 324 ; 324 ; 323 311 302 ! 282 281 313 87 | 286 285 296 | 300 296 315 ; 315 306 291 310 315 318 320 331 324 319 317 319 321 ( 317 311 300 292 285. ; 308 88 274 283 298 j 303 308 316 \ 320 321 315 315 320 318 : 318 320 321 321 321 I 321 323 j 316 I 303 ; 302 ' 296 284 j 310 89 283 289 298 j 308 317 ( 328 ( 329 i 323 294 311 314 323 ( 319 337 318 316 318 319 319 ( 319 j 317 ( 310 301 283 ( 309 .. 278 286 291 ! 303 312 j 317 ' 315 315 315 319 320 320 j 315 I 320 317 317 318 316 317 j 315 i 307 j 297 286 281 308 I li|!

C— la

18

Table of Hourly Values (Greenwich Mean Civil Time)— continued.

Magnetic Declination (east of north) ■ 18° + tabular minutes. Day of Month. '*°- oi \ oh. : Day. | lh. I 2h. 3h. 4h. j 5h. | 6h. ; 7h. 8h. ( 9h. ! lOh. llh. I 12h. 13h. j 14h. '< 15h. ! 16h. ! LJ ' I i I i I nil. 18h. : 19h. 20h. 2ih. i 22li. 23h. IMean. i I ! I i i I , - i , l ■ i I • l i i ■ i I i 1918 April 1 „ 3 .. 4 ,, 6 7 .. 8 „ 9 „ 10 „ 11 „ 12 ., 13 ,, 14 ,. 15 „ 16 „ 17 .. 18 ,, 19 „ 20 90 I 54-8 57-6 ( 59-9 59-9 I 58-8 \ 57-4 56-5 56-1 55-9 55-7 55-4 53-0 52-6 54-3 5*7 54-7 55-1 55-1 54-9 54-2 ( 51-8 50-6 j 48-5 50-6(54-9 91 54-8 57-9 ! 60-5 61-2 ! 61-6 i 59-1 j 55-1 ; 54-1 : 54-6 53-7 541 52-9 51-3 53-7 53-4 55-6 54-2 54-7 54-3 53-4 50-6 49-4 j 49-2 i 52-2 i 54-7 92 55-3 58-0 j 59-6 60-2 ; 59-2 j 57-4 55-9 56-2 55-9 55-9 ( 55-2 54-8 54-7 54-8 55-1 I 55-2 55-2 ( 55-3 ( 55-3 \ 54-5 j 51-1 49-9 48-1 j 51-0 i 55-2 93 55-7 60-51614 63-1 62-6 j 61-1 57-7 I 57-3 : 53-5 54-5. 1 55-2 I 54-8 53-9 | 544 544 54-3 55-9 j 55-5 ( 56-2 I 54-9 : 52-8 514 511 52-2 56-0 94 55-5 57-7 I 58-2 61-4 61-6 : 60-5 57-2 54-5 53-7 54-8 52-3 51-4 48-5 51-9 54-2 ! 54-1 58-2 ( 56-4 j 58-4 j 57-1 ' 55-9 54-4 | 52-0 53-7 j 55-6 95 57-1 | 59-7 ( 62-5 62-3 [ 63-3 j 594 57-2 : 56-9 54-8 52-6 44-1 48-6 48-1 40-8 48-8 j 51-4 54-2 } 55-7 \ 56-5 | 55-4 ( 53-3 j 53-7 [ 51-3 51-4 j 54-1 96 54-8 59-3 ( 60-0 63-5 ( 63-3 ' 58-7 58-3 55-7 55-5 54-2 i 53-3 52-8 53-3 53-7 , 56-5 55-3 56-1 55-7 ( 55-4 54-5 ! 52-6 i 50-3 I 49-9 , 51-8 55-6 97 54-8 57-9 59-8 60-8 59-8 i 58-0 56-3 56-3 55-9 55-3 \ 54-3 54-5 54-8 53-9 54-3 55-1 55-2 55-4 j 55-9 59-8 ( 55-8 52-6 i 52-0 | 52-9 55-9 98 54-8 : 57-5 59-8 59-7 58-4 j 57-9 57-6 56-4 55-7 55 6 54-6 50-9 54-4 55-5 53-9 55-2 54-1 54-4 | 54-3 I 53-3 ■ 52-1 51-7 ! 50-3 : 52-2 550 99 55-9 : 58-9 60-5 60-6 58-7 ( 56-6 ' 54-8 54-8 54-4 55-1 54-8 54-1 55-2 55-1 55-9 55-2 56-3 ' 55-5 ( 54-4 ; 53-6 j 51-8 : 50-3 50-3 514 ( 55-2 .. 100 54-8 ! 57-5 61-1 62-3 60-5 59-3 554 54-3 55-9 54-8 55-5 52-8 ( 49-8 - 47-5 i 51-7 j 43-0 47-5 , 53-3 55-4 | 57-7 l 54-5 52-1 54-8 i 55-1 i 54-4 .. 101 57-9 60-7 61-1 60-5 ( 59-3 56-9 55-8 55-5 55-1 46-5 ( 53-0 54-2 54-6 54-8 ( 54-2 I 55-3 55-2 ; 544 55-9 I 55-6 52-6 51-3 51-4 ! 531 55-2 102 56-2 58-2 60-0 59-9 59-3 ; 58-2 57-1 56-4 55-5 55-9 55-3 55-1 55-3 54-7 55-3 j 55-3 55-3 j 55-2 ( 54-8 ( 54-4 53-1 514 51-0 51-4 1 55-« .. 103 54-6 57-6 59-3 59-3 \ 58-5 | 57-9 57-2 56-5 56-3 55-6 ; 54-9 55-3 54-7 54-8 54-7 ! 54-5 54-5 | 54-8 \ 54-8 54-6 ' 53-5 51-8 I 51-2 51-0 \ 55-3 .. j 104 53-9 57-7 61-2 61-8 60-5 j 58-2 56-6 55-9 55-9 55-2 54-8 54-7 54-4 53-4 53-7 54-7 55-3 55-2 ; 544 55-2 53-7 53-3 52-3 53-0 55-6 .. 105 54-5 56-7:58-4 58-7 , 57-5 56-6 56-2 56-1 55-9 156-1 ] 54-8 54-3 54-5 54-3 54-2 : 54-2 54-1 ( 55-2 54-2 54-3 53-5 52-3(51-3 51-9 55-0 .. 106 54-5 56-7 , 58-7 i 59-0 I 58-2 571 j 56-2 55-9 55-7 I 55-9 I 55-5 j 55-2 | 55-1 i 55-1 55-1 I 55-1 55-2 : 54-6 | 55-2 : 54-8 53-4 51-6 ! 51-6 52-6 I 55-3 .. 107 54-8 58-2 59-8 60-2 I 59-8 ( 58-2 ! 56-7 55-9 i 55-7 I 55-6 ! 554 ( 55-1 | 55-2 55-2 54-7 : 51-8 53-5 : 53-8 54-7 54-3 j 53-5 52-1 i 51-8 52-3 j 55-3 108 54-9 59-1 59-1 59-8 ( 60-5 j 62-3 62-7 51-4 55-9 55-7 54-5 43-4 : 50-9 53-0 55-8 56-6 54-9 ! 55-9 55-5 55-1 ! 54-4 52-6 : 51-7 '■ 52-2 ! 55-3 .. 109 54-1 55-9 : 57-4 58-2 ' 58-1 ] 57-2 55-9 55-6 55-5 ; 55-6 55-2 54-1 , 54-2 54-8 ! 54-9 55-2 55-4 : 55-3 55-4 54-9 j 54-5 ; 53-5 52-6 52-2 ( 55-2 „ 21 „ 22 ., 23 „ 24 ., 25 .. 26 „ 27 „ 28 ., 29 „ 30 Means .. 110 54-1 56-4 58-2 58-4 58-2 57-1 56-4 55-7 55-6 55-2 ! 54-8 ; 54-8 54-8 54-7 55-3 55-7 55-8 55-7 '> 55-5 ; 54-9 : 53-7 534 j 53-1 ! 53-7 55-5 .. Ill 55-8 58-2 59-2 j 59-3 ( 58-2 57-1 55-5 I 55-1 54-6 54-5 54-7 53-4 ( 54-1 54-7 j 55-3 - 55-4 554 55-6 I 55-5 I 55-4 54-3 52-8 \ 52-2 j 53-4 55-4 . .-. 112 55-1 59-1 60-9 ! 57-9 j 59-9 ; 59-3 i 56-4 ( 57-2 55-9 44-3 ! 53 1 53-9 ( 55-4 53-9 ( 55-1 ( 55-5 55-3 : 55-4 ; 55-5 ] 55-9 54-6 ; 534 ( 52-6 I 53-1 55-4 .. 113 55-2 57-6 59-2 : 58-8 58-2 56-9 55-9 i 55-7 55-6 52-6 54-6 53-8 53-7 544 i 54-4 : 55-4 55-5 55-4 55-4 54-9 i 54-1 j 52-6 | 52-3 531 55-2 .. 114 55-6 58-3 60-6 61-0 59-6 58-5 56-9 55-9 55-5 55-3 54-6 54-6 54-6 54-2 : 55-5, 55-9 57-5 55-4 55-2 564 55-9 53-7 53-7 54-8 56-2 .. 115 54-8 58-2 \ 59-3 59-9 59-3 57-9 54-8 55-3 50-3 51-4 49-4 514 51-4 52-0 52-3 j 53-7 54-3 53-7 56-5 55-1 53-7 52-0 ■ 51-0 52-7 54-2 .. 116 55-4 57-6 59-3 59-3 60-1 58-5 57-1 55-9 55-6 51-7 53-7 52-6 54-2 55-5 55-7 55-3 56-3 55-9 554 54-8 54-2 53-9 52-9 ; 53-1 i 55-6 .. 117 55-9 i 58-3 I 60-1 60-2 59-3 58-0 57-4 57-1 57-3 ( 55-9 54-8 54-8 j 54-8 54-4 \ 55-4 55-4 55-2 55-1 55-1 54-8 53-7 52-7 52-2 52-7 I 55-9 .. 118 54-7 57-3 58-2 58-2 57-9 56-9 56-1 55-9 55-7 ( 55-6 55-3 55-2 \ 551 55-3 I 554 554 55-1 554 55-3 54-7 53-9 52-6 514 53-5 554 .. 119 55-9 58 2:59-3 59 3 58-2 58-2 56-9 i 52-6 52-6 ( 51-0 50-6 51-2 50*3 54-8 55-6 54-4 57-3 56-2 58-3 58-2 56-7 55-6 54-1 55-2 55-5 .. 55-2 58-1 I 59-8 I 60-2 59-6 58-2 56-7 55-6 55-2 54-1 53-9 53-3 53-5 ( 53-7 j 54-5 54-5 551 55-2 554 55-2 53-6 52-3 51-6 52-7 55-3 ' i-l : ' ■ [ ; I I I J : '

19

C—la

Table of Hourly Values (Greenwich Mean Civil Time)— continued.

Magnetic Horizontal Force : 0-22000 C.G.S. + tabular y. Day of Month. | N °- of i Oh. I 11,. I 2h. 3h. ; 4h. 5h. 6h. , 7h. 8h. 9h. lOh. I ' llh. 12h. 13h. 14h. | 15h. 16h. j 17h. 18h. 19h. 20h. 21h. 22h. I I I I I 23h. Mean. 1918. April 1 „ 2 „ 3 ,, 4 ,. 5 90 264 277 293 310 320 91 281 ! 283 291 293 \ 302 92 : 288 294 | 300 310 ( 318 93 269 271 284 293 301 94 249 271 269 284 294 322 ; 320 317 317 326 326 331 332 324 ; 326 ( 326 326 327 328 302 i 286 307 315 317 319 313 307 315 ! 316 321 319 i 317 323 322 i 324 327 333 333 332 332 319 323 ; 323 320 322 325 325 298 - 29S 301 289 305 316 ! 317 318 319 ! 325 314 314 ! 314 319 281 ; 272 290 294 305 315 310 295 297 299 302 316 322 310 325 I 319 304 297 289 314 : 323 > 314 307 294 284 306 1 328 324 317 300 275 317 320 317 325 278 268 303 302 . 295 282 266 242 290 „ 6 ,, 7 ,. 8 ,, 9 „ 10 95 231 226 225 251 246 96 208 222 231 248 273 97 246 245 265 275 | 291 98 265 269 277 288 302 99 270 277 283 295 ! 299 272 261 282 291 275 | 276 251 255 308 295 298 274 291 275 272 262 273 276 267 277 278 283 286 292 293 292 295 299 293 290 > 304 306 304 299 306 306 312 317 311 313 316 318 306 ! 283 I 295 309 309 304 : 318 299 309 324 313 307 307 311 298 303 299 297 302 317 328 314 309 315 309 306 311 313 - 284 283 264 : 256 i 243 267 j 301 297 291 275 252 263 311 324 302 276 265 296 311 307 295 284 270 298 313 j 31.1 311 303 287 303 278 ( 261 ( 227 232 222 289 304 I 298 295 281 273 281 307 306 294 275 262 296 310 308 302 297 287 302 317 316 , 310 301 294 310 ., 11 „ 12 „ 13 „ 14 „ 15 ..100 '258 27 293 307 . 302 .. I 101 224 221 253 266 271 . . 102 263 263 , 272 283 294 .. 103 271 278 ' 287 292 ( 298 .. I 104 276 275 j 291 i 303 302 305 297 312 317 322 326 314 306 297 | 303 ' 309 I 293 280 293 269 | 275 276 282 293 284 290 293 291 299 , 301 305 , 307 301 29S I 301 305 : 307 j 305 306 306 308 308 306 307 308 I 308 309 305 : 306 310 308 ' 312 308 310 310 305 306 306 309 j 309 309 317 319 320 319 320 314 322 318 317 j 313 315 316 317 318 „ 16 ,, 17 „ 18 ,. 19 „ 20 „ 21 22 ',', 23 „ 24 „ 25 „ 26 ., 27 „ 28 •„ 29 „ 30 Means .. I 105 292 292 296 302 309 .. | 106 291 290 295 300 311 .. 107 293 ■ 28S 293 296 301 .. j 108 267 266 292 : 296 295 .. j 109 271 272 279 282 292 .. 110 298 296 291 299 307 .. Ill 289 288 292 295 306 .. 112 288 30ii 297 292 305 .. 113 287 288 289 294 305 .. 114 298 293 269 301 300 .. 115 233 233 233 248 252 .. 116 272 277 2»2 ' 280 278 .. 117 289 291 297 302 311 .. i 118 290 289 ; 294 298 304 .. 119 304 306 310 311 304 _ - : .. 271 | 274 ! 281 | 290 296 314 317 319 321 321 320 320 321 322 318 318 313 313 323 314 313 319 321 324 323 323 323 j 321 322 323 324 322 329 308 313 323 327 328 331 330 324 325 324 317 306 313 321 273 : 268 310 297 307 310 317 325 291 283 285 288 287 292 296 301 309 309 310 308 311 310 307 307 308 310 312 314 309 313 313 316 316 316 317 323 322 '■■ 322 ( 326 327 327 329 316 312 308 312 319 317 317 317 316 317 319 319 317 321 305 309 310 300 271 290 309 308 310 306 ( 319 311 309 310 306 308 312 309 306 310 310 . 306 311 314 j 310 . 309 313 i 316 313 316 318 322 332 , 322 321 321 326 326 j 324 325 333 332 247 251 254 273 318 311 292 285 297 j 287 ! 298 : 297 293 291 287 287 294 300 294 298 299 305 305 306 ( 307 310 310 311 312 313 316 313 308 308 313 312 309 308 ! 316 314 311 313 311 310 314 318 318 317 316 316 314 313(314 314 315 316 285 285 214 26 271 272 295 305 290 291 293 293 304 299 299 297 303 305 308 309 311 307 310 310 311 309 311 312 322 322 ! 313 298 296 313 325 331 321 306 295 315 329 338 318 305 286 314 296 296 292 284 j 281 ! 299 314 314 310 304 ! 298 302 333 i 330 320 308 395 315 322 324 315 301 287 310 305 319 307 299 I 294 303 314 318 314 306 | 298 I 306 328 | 313 299 ! 257 ' 219 i 309 297 j 285 - 284 i 283 i 277 276 312 I 312 ; 309 296 , 288 297 309 307 ! 294 285 ( 285 306 314 : 316 311 317 : 315 311 311 301 293 - 294 282 292 312 310 i 301 ! 289 I 277 300 i i

C—la.

Table of Hourly Values (Greenwich Mean Civil Time)-continued.

20

agne if'eel ma ion eas' norl ;a iul lar nunu ,es. Day of Month. o£ ! Oh. I lh. Day. I ; I 2h. 3h. 4h. | oh. III. I oh. ! I i 7h. : 8h. 9h. 10h. lib. ; i2h. ' i3b. i | I ! I 14h. ' 15b. I6h. 17h. 18h. : 19h. 1 I 20h. 21h. I 22h. | 23b. 'Mean. I 1918. Mav 1 .. 2 .. 3 „ 4 „ 7 ,. 9- „ 10 ,. 11 ,, 12 ,. 13 .. 14 ,. 15 || I I I I I I ' I I I .. 120 57-6 59-0 60-5 ] 58-0 60-5 i 58-7 ' 49-8 55-9 i 54-6 j 54-1 i 54-5 53-8 54-1 I 55-6 55-8 55-8 i 55-5 55-5 55-3 ! 55-7 : 54-6 52-6 j 52-2 53-4 55-5 .. 121 55-2 58-2 60-7 60-1 60-1 I 58-0 ( 56-2 55-9 55-4 55-6 54-5 54-6 55-2 55-5 55-7 55-6 55-6 55-5 55-3 54-8 53-9 52-3 52-2 53-4 55-8 .. 122 55-3 57-3 60-1 60-1 59-0 55-7 ' 55-7 55-9 55-6 554 j 54-3 I 52-5 j 54-7 i 55-2 '< 55-3 57-5 55-7 55-6 554 : 54-9 53-8 53-1 52-2 52-8 55-5 .. 123 54-1 57-1 59-6 59-3 59-0 57-1 53-0 55-6 54-5 53-7 53-7 I 49-2 j 50-9 ; 50-3 1 52-6 53-3 55-4 56-2 56-6 55-3 54-4 53-1 52-6 52-2 54-5 .. 124 53-3 56-5 58-0 59-3 59-9 59-7 , 58-5 58-0 52-0 ; 55-5 55-2 ! 55-3 ( 54-8 ( 55-5 ( 54-2 53-0 54-8 56-4 56-7 55-5 53-9 53-4 : 53-5 i 544 55-7 .. 125 55-9 57-6 59-1 , 58-2 57-4 56-9 55-9 , 55-9 56-1 55-9 55-7 : 55-5 55-5 54-6 54-8 55-7 55-8 55-9 55-5 54-8 53-9 52-7 52-3 , 51-7 55-6 .. 126 54-3 57-0 59-2 : 59-3 59-1 57-3 ' 56-7 I 55-9 55-9 55-9 55-7 : 55-3 55-5 55-9 55-8 55-8 55-5 55-3 54-7 ! 544 53-1 51-8 51-7 : 51-7 55-5 .. 127 53-6 56-3 58-5 59-2 ( 58-2 1 57-1 56-2 ' 55-9 55-9 55-9 54-9 i 55-1 i 55-4 55-5 55-9 57-1 55-9 55-9 55-3 54-7 53-8 52-5 52-6 i 53-1 55-6 .. 128 ! 55-7 58-9 60-2 59-8 ! 58-3 : 57-1 55-9 55-9 I 55-8 55-7 55-1 : 54-9 ! 54-9 j 55-4 55-4 55-4 55-5 55-5 55-2 54-3 53-7 534 52-2 i 52-7 j 55-7 .. 129 54-2 57-0 60-2 60-7 ( 60-8 ( 59-2 57-1 56-1 55-4 55-1 54-8 54-3 54-9 55-7 55-7 55-5 ( 55-4 55-5 55-3 54-8 54-9 53-7 53-0 52-9 j 55-9 .. 130 | 53-7 57-1 58-8 59-1 ■ 58-0 i 57-2 1 56-1 55-9 55-3 54-7 52-7 52-0 53-7 54-8 54-8 55-8 55-4 56-9 56-1 55-3 54-3 56-1 53-5 53-1 554 .. i 131 54-7 57-5 60-7 60-5 | 59-3 I 57-9 56-3 56-2 56-6 55-4 53-7 50-9 ; 53-1 53-0 ! 54-3 53-5 55-1 ; 55-6 55-4 ; 54-9 ] 54-5 53-3 51-9 j 52-2 , 55-3 .. ; 132 ( 54-3 57-6 : 58-3 60-2 60-3 59-9 57-1 58-1 55-8 I 55-3 53-1 54-2 54-3 54-5 54-7 54-4 57-0 55-2 54-9 55-3 54-8 53-5 52-6 ( 53-4 55-7 .. 133 54-8 56-3 58-7 58-9 58-8 57-6 56-1 55-8 54-9 55-9 53-0 53-6 53-8 56-4 ; 54-8 55-7 56-5 55-4 55-4 55-4 54-6 53-4 '. 53-5 ( 54-3 ! 55-6 .. 134 j 55-3! 56-1 58-1 58-3 ! 58-0 57-1 54-5 i 54-6 54-9 52-8 53-3 51-3 52-7 53-6 ' 551 54-9 57-1 61-1 58-7 58-0 564 56-3 55-2 I 55-2 I 55-8 . ,. 16 ,, 17 „ 18 ,, 19 „ 20 „ 21 „ 22 ,.- 23 ,. 24 „ 25 „ 26 ., 27 ,, 28 » 29 „ 30 „ 31 Means .. 135 : 55-8 574 584 58-2 ! 58-1 ; 56-7 55-7 - 55-9 55-8 55-5 54-9 54-7 54-6 54-9 ] 55-4 55-9 : 56-4 55-4 55-9 60-5 61-2 • 57-0 614 ' 57-9 56-8 .. 136 57-0 i 59-1 59-9 62-8 61-6 59-9 57-3 54-6 54-3 . 52-8 51-6 48-8 i 48-9 47-0 51-6: 58-2 55-9 56-3 56-1 56-3 -56-1 55-7 55-7 55-9 > 55-6 ... 137 58-0 I 58-1 60-1 584 | 57-2 i 48-8 55-3 - 55-2 54-8 , 49-6 51-7 54-8 51-9 f 55-3 54-6 '■■ 59-4 58-2 , 58-1 57-1 56-3 55-4 554 55-9 j 57-1 55-7 .. 138 56-3 j 57-7 58-8 56-9 j 56-4 ' 55-4 54-9 53-5 55-5 48-5 52-3 ' 54-7 54-2 ' 57-1 56-9 55-4 58-2 : 56-1 56-4 56-2 56-4 55-8 54-8 54-9 I 55-6 .. 139 55-3 1 57-6 57-1 57-7 56-3! 54-9 53-6 ( 53-5 54-9 54-5 52-7 52-3 54-2 54-9 55-4 57-9 57-3 56-4 56-4 56-4 56-1 I 55-9 55-1 : 54-7 55-5 .. 140 | 56-3 56-7 57-3 57-6 57-1 52-1 53-1 53-3 54-6 ; 53-5 52-1 53-8 54-4 55-2 57-1 55-9 55-7 , 55-3 55-5 54-8 54-6 53-9 53-9 54-7 54-9 .. j 141 55-3 57-1 58-0 : 58-2 : 57-1 I 56-1 | 55-6 55-9 55-1 ! 55-3 54-9 55-3 ' 54-9 55-5 ; 55-6 55-5 55-9 55-9 55-7 55-3 ! 55-1 53-7 . 53-7 54-8 ; 55-6 .. 142 56-5 57-1 57-3 58-0 57-2 56-7 55-6 54-3 55-9 ( 54-8 ( 52-5 53-5 53-7 54-9 55-4 55-4 55-8 55-8 55-5 55-3 54-8 54-3 53-5 53-6 55-3 .. 143 53-7 55-3 57-6 I 58-3 ( 58-2 i 56-2 | 55-4 56-4 55-8 ! 54-9 : 54-6 54-6 54-8 54-9 j 55-5 - 55-7 55-9 ' 55-9 55-8 55-7 55-1 53-8 53-7 j 54-5 < 55-5 .. 144 54-8 55-9 57-6 58-4 58-2 56-3 55-9 55-9 55-4 i 55-3 ! 53-7 53-5 54-1 54-4 ( 55-4 56-4 56-9 55-9 56-5 55-5 55-4 54-6 53-7 ( 53-5 I 55-6 .. 145 54-2 ( 56-1 58-1 58-8 58-7 57-0 ' 56-2 55-9 55-8 55-3 55-3 53-0 54-6 54-6 ( 55-3 ; 55-7 55-9 55-8 ! 55-9 55-5 554 54-3 53-6 54-1 ] 55-6 .. (146 54-8 1 56-1 57-5 57-6 57-6 , 56-6 55-4 55-5 55-3 55-5 ( 55-3 54-9 ( 55-3 554 55-2 56-1 55-9 55-8 , 55-5 55-6 54-9 54-3 53-5 53-6 | 55-6 .. I 147 53-8 I 54-8 57-7 ' 58-2 : 57-9 ! 56-4 55-4 - 55-9 55-9 j 56-1 55-1 54-9 ' 54-8 53-6 I 54-8 55-5 55-9 56-1 ' 56-1 55-9 55-7 55-1 54-6 54-7 ! 55-6 .. 148 55-5 I 56-9 58-2 58-4 57-2 57-5 57-6 58-3 59-1 55-7 54-7 : 54-8 I 54-7 52-6 54-8 52-0 54-2 54-7 55-2 56-1 60-1 58-2 57-0 56-6 i 56-2. .. 149 57-5 | 57-0 58-2 584 57-1 55-9 55-6 55-8 54-8 50-9 53-5 : 53-8 ( 54-6 51-4 54-3 I 54-6 i 55-5 - 56-1 56-7 55-8 55-9 54-6 54-6 ' 55-1 55-3 .. 150 55-5 55-9 57-3 57-9 j 57-3 I 56-5 55-4 55-9 : . 55-4 , 55-6 54-6 54-9 54-8 54-9 55-4 ' 55-5 55-7 55-8 55-6 56-7 54-9 54-8 54-6 ( 54-5 55-6 ' ! I ■ ' _ : I : ! I ! ( .. ( 55-2 56-7 58-6 58-9 58-4 56-9 55-6 55-7 i 554 54-5 540 53-7 54-1 ( 54-5 55-1 \ 55-6 56-0 560 55-9 55-7 55-2 54-3 53-9 : 54-1 55-6

C—la

21

Table of Hourly Values (Greenwich Mean Civil Time)— continued.

Magnetic Horizontal Force : 0-22000 C.G.S. + tabular y. Day of Month. 'N^ 0 * Oh. lh. : 2h. ! 31i. 4h. oh. I 6h. 7h. , 8h. | | I i I | 9h. lOh. llh. 12h. 13h. i ; 14h. : 15h. 16h. 17b. 18h. | 19h. 20h. ! 21h. 1 i 22b. 23h. Mean. 1918. Mav 1 „ 2 ,, 3 ., 4 „ 5 .. 120 260 : 261 266 285 270 281 : 301 281 284 290 299 306 304 298 298 : 299 301 305 307 303 297 293 291 284 290 .. 121 ( 275 262 264 ■ 275 287 303 j 304 300 299 306 308 310 311 310 309.309 313,313 315 315 315 306 294 287 300 .. 122 271 268 283 ! 282 295 298 i 309 317 317 317 ; 315 312 ' 310 308 312 ' 322 320 : 310 312 317 318 311 298 288 305 .. 123 283 291 288 ! 287 296 282 290 281 274 288 288 287 288 283 - 295 297 298 299 300 300 307 304 299 291 ' 299 .. 124 ( 292 : 297 282 ( 280 274 , 269 272 264 288 290 305 307 305 : 314 318 314 311 309 303 318 316 314 307 299 298 ,. 6 ,- 7 „ 8 ,. 9 „ 10 .. | 125 303 299 299 295 295 301 , 306 311 313 j 321 316:318 319 311 305 308 309 309 313 314 317 312 306 297 308 .. - 126 | 292 ; 288 291 297 ; 302 303 305 307 312 ' 317 : 318 '■ 318 310 ( 318 317 319 317 318 320 320 320 318 310 303 310 .. 127 293 287 294 298 306 312 310 308 309 306 : 314 ( 319 319 : 314 314 324 321 318 - 320 320 321 314 308 302 310 .. 128 306 300 293 304 319 321 i 320 324 320 323 i 321 ( 322 323 319 320 317 316 320 323 322 i 324 319 j 310 307 316 .. 129 295 288 293 301 313 309 i 321 321 325 326 319 321 321 316 ! 318 316 316 318 ! 322 321 ( 330 329 ( 321 313 316 ,- 11 „ 12 „ 13 „ 14 „ 15 .. 130 305 298 302 307 317 322 322 324 32-1 311 300 310 307 308 312 311 312 314 314 320 319 311 316(301 312 .. ! 131 283 ! 277 278 ' 279 301 312 315 315 310 297 303 306 308 \ 305 305 307 309 309 311 312 , 318 315 '■■ 311 ! 298 304 .. ( 132 298 287 285 299 313 304 313 316 319 320 311 315 313 316 314 313 328 319 316 314 317 316 ; 314 313 311 .. : 133 309 ' 308 ( 309 314 315 319 315 325 312 310 328 ; 306 302 305 319 310 ! 313 315 317 320 : 321 316 j 308 300 313 .. j 134 293 291 298 302 311 316 311 311 305 295 299 297 309 308 310 326 I 323 306 329 323 i 318 308 ! 327 319 . 310 „ 16 >, 17 „ 18 ,, 19 „ 20 „ 21 „ 22 ,, 23 ,, 24 ,, 25 » 26 ,- 27 „ 28 . „ 29 „ 30 „ 31 Means .. ! 135 I 297 ( 268 ; 283 [ 290 296 . 306 i 303 299 306 312 316 | 321 j 311 318 j 319 323 | 325 i 327 332 334 , 307 291 , 258 ,229 303 .. 136 218 222 i 213 ' 240 210 229 ' 198 I 219 - 210 234 242 260 ' 266 274 ! 249 255 258 265 270 272 I 254 : 217 259 244 241 .. 137 238 255 253 i 245 273 263 273 : 273 282 ! 331 278 299 297 292 ( 282 279 287 282 290 286 293 284 251 258 277 .. 138 274 279 254 | 273 278 284 ] 290 298 291 : 302 288 292 293 : 298 i 301 311 287 292 296 289 i 301 298 291 281 289 .. 139 272 263 280 I 285 278 289 295 305 295 294 303 301 298 : 296 ! 298 306 303 300 302 294 ' 297 . 301 291 279 293 .. 140 f 280 I 269 281 287 286 I 295 284 291 299 292 309 309 300 301 : 312 302 298 300 302 300 305 j 306 306 295 296 .. 141.293:287 286:297:302 307 303 297 287 301 307 314 311 308 308 307 308 307 311 312 318 321 320 303 305 .. 142 290 I 299 297 305(310 309 311,309 314 305 305 315 304 305 309 305 309 309 313 314 319 323 324 319 309 .. 143 308 ! 302 299 303 ! 308 312 308 312 308 316 307 306 309 319 - 316 317 321 322 323 323 325 326 325 319 314 .. 144 310 : 306 304 : 308 I 308 309 312 313 317 317 304 306 304 304 307 309 313 312 309 313 313 313 308 299 309 .. 145 394 i 292 288 '< 290 301 309 309 309 313 313 309 312 307 314 312 313 312 313 314 316 319 319 314 ! 305 312 .. 146 295 ! 298 303 305 I 310 316 315 316 317 317 321 319 316 312 312 310 313 319 319 320 324 325 323 : 319 314 .. 147 ! 311 311 311 ; 312 ( 318 323:320 322 321 314 1318 317 315 315 315 315 316 317 319 321 327 328 328 324 318 .. 148 317 306 307 312 319 328 ' 318 : 303 295 307 320 307 310 - 308 313 321 313 315 320 322 318 : 322 314 308 313 .. 149 312 289 288 j 291 292 ( 307 309 ( 310 ; 292 315 308 302 325 302 299 306 303 307 316 ; 308 311 : 313 306 303 305 .. 150 301 299 298 j 299 306 309 312 306 306 303 304 306 308 307 308 308 309 310 312 312 318 317 317 307 308 .. 292 I 285 I 286 i 292 297 I 302 302 > 303 302 306 306 308 307 307 307 309 '' 309 309 312 312 313 I 309 i 305 I 297 303 i I III .. i !

C—la

22

Table of Hourly Values (Greenwich Mean Civil Time)— continued.

Magnetic Declination (east of north) - 16° + tabular minutes. Day oi Month. N°- of i Oh. ' l lh. Day. ' 2h. j 3h. ' 4h. . 5h. I 6h. 7h. 8h. I I I 9h. | lOh. llh. 12h. I ! i 13h. 14h. I6h. 16h. 17h. ISh. 19h. 20h. 21h. 22h. 23k. Mean. I I i i • - I 55-7 55-9 j 55-9 55-9 55-7 i 54-9 55-5 55-8 55-6 55-3 : 55-4 55-4 55-9 554 55-3 I 56-4 56-5 56-5 55-9 55-5 ! | ' 55-2 54-8 54-3 53-4 j 55-5 > 54-8 54-6 53-5 54-6 j 55-8 I 551 54-3 53-7 53-9 l 55-9 i 54-8 i 54-3 53-7 53-7 55-9 1918. Fune 1 ., 2 „ 3 ., 4 .. 151 .. I 152 .. ! 153 .. I 154 l _- . __„:_„. .. ., 55-4 ' 55-9 570 58-1 54-8 ! 57-0 54-6 57-1 58-8 58-7 58-1 56-9 55-4 57-1 58-8 59-1 58-2 57-3 54-8 56-2 58-7 58-8 57-6 56-4 r 55-9 56-1 55-3 < 55-8 55-9 55-7 i 57-1 56-6 55-9 55-9 55-9 | 55-9 ; 554 55-1 54-6 54-5 54-8 54-9 55-9 55-3 55-2 | 55-4 i 55-2 55-9 55-8 I 554 54-8 j 54-9 ( 55-4 ( 55-4 55-9 : 55-9 55-9 | 55-4 ! 55-6 | 56-3 ,, 5 ,. 6 7 8 9 .. 155 .. 156 .. 157 .. 158 .. 159 54-5 ; 56-2 59-2 59-8 58-8 ( 57-1 55-3 ' 55-9 56-5 57-9 57-1 56-6 55-9 57-1 60-1 59-3 57-6 57-3 55-5 55-9 58-2 58-9 58-2 57-1 55-4 ; 57-1 i 57-7 i 58-8 58-4 56-7 55-9 55-9 55-5 55-5 564 56-4 56-6 56-5 54-3 56-5 55-9 55-5 i 55-9 55-7 55-4 55-9 55-9 55-9 ( 55-9 55-9 56-2 55-9 55-4 55-4 55-3 55-4 55-4 55-4 54-8 54-4 j 54-3 55-4 55-5 55-5 55-4 55-4 I 53-3 54-3 55-4 55-4 55-3 55-4 ; 55-4 55-4 55-4 56-3 55-9 55-9 55-4 55-4 554 55-9 [ 55-4 55-5 55-4 55-5 55-4 55-3 55-9 54-9 56-4 55-7 55-4 55-4 554 j 54-4 55-9 : 55-3 55-4 56-9 ! 55-4 54-3 54-3 54-8 : 56-1 55-4 54-8 54-4 55-3 55-6 54-3 53-7 53-7 53-7 55-7 55-3 54-8 54-8 54-8 I 55-8 55-4 55-4 58-2 58-8 l 56-3 ,, 10 ,, 11 „ 12 „ 13 „ 14 .. 160 .. 161 .. 162 .. 163 .. 164 58-1 59-3 60-4 58-8 60-0 59-6 57-6 : 57-3 57-7 56-9 57-5 57-1 54-8 56-6 j 55-4 56-5 56-6 j 55-5 57-1 56-5 ( 55-9 57-6 57-5 j 56-5 55-4 57-1 : 58-7 59-7 57-1 57-0 58-2 56-9 50-9 55-9 55-5 55-7 56-5 56-5 i 53-9 55-5 55-9 ( 55-5 51-2 56-5 j 53-7 45-2 ! 43-0 46-4 56-5 53-1 49-6 55-9 i 53-1 514 53-7 55-5 54-2 52-0 l 55-3 55-3 ( 54-1 54-8 55-4 55-5 55-4 55-4 I 55-4 55-4 55-9 53-8 53-1 53-1 52-1 554 52-1 „H __H „._.._. - 57-1 57-1 59-3 58-8 59-9 55-4 58-8 57-3 56-5 56-5 56-5 56-5 58-2 59-9 58-7 56-4 56-5 56-5 56-4 55-9 53-7 55-9 ! 56-5 | 56-5 55-9 60-0 59-9 57-1 l 58-2 ! 56-0 55-9 54-4 54-3 54-9 55-8 58-8 56-5 56-6 56-5 ; 56-1 55-9 : 55-5 54-8 54-8 56-0 55-9 54-8 54-8 : 54-8 55-2 ,. 15 ,. 16 „ 17 „ 18 .., 19 .. 165 .. 166 .. 167 .. 168 .. 169 55-9 55-9 i 57-6 571 57-1 51-3 58-2 58-8 59-3 59-3 53-1 464 57-1 58-2 58-2 57-5 57-2 53-1 57-1 57-4 58-4 56-5 ( 57-2 j 54-3 55-5 ! 57-6 ! 58-8 ; 57-7 j 57-3 55-9 55-4 57-1 ( 58-7 58-8 ( 57-6 56-4 56-3 ! 57-1 58-5 59-3 57-7 I 56-2 56-8 57-7 i 58-2 58-9 58-2 ' 58-2 54-3 55-9 ( 52-0 57-6 57-6 ( 56-5 55-9 I 57-9 59-3 ; 59-3 I 58-8 i 57-1 54-8 56-5 40-8 56-4 56-5 53-7 49-2 54-2 55-4 55-5 55-5 I 54-3 54-8 55-8 52-6 ... . - . ! . 54-2 55-3 53-7 54-3 54-2 55-4 53-3 53-7 53-7 j 54-3 53-9 56-4 54-3 ( 554 55-4 j 55-3 54-8 55-1 54-8 ! 55-1 55-3 554 55-7 56-5 55-4 55-4 554 , 554 554 554 I 58-8 57-7 58-2 ( 59-3 j 57-6 55-4 54-4 i 57-1 I 56-5 ( 58-7 57-1 55-9 j 56-5 55-9 ( 56-5 56-6 56-5 56-2 56-2 | 55-9 55-9 I 56-5 56-4 j 55-9 j 55-7 I 58-2 57-6 57-1 57-6 55-7 58-2 57-5 56-2 57-1 55-8 57-1 55-4 55-9 57-6 55-8 55-7 ! 54-8 54-3 54-3 i 55-8 ( 55-4 54-8 54-3 I 54-3 I 55-7 „ 20 „ 21 ,. 22 „ 23 „ 24 .. 170 .. 171 .. 172 .. 173 .. 174 55-4 55-9 55-9 55-4 55-9 ( 55-4 56-5 ! 55-3 ; 56-5 55-9 I 55-9 I 55-4 56-5(57-1 57-1 564 55-5 54-8 54-2 54-8 55-9 55-4 55-3 55-4 55-1 55-4 554 52-5 54-8 55-4 55-4 55-9 56-5 55-4 55-4 55-8 55-4 55-9 56-5 56-6 | 58-1 58-2 54-6 554 55-9 | 57-4 56-5 : 56-5 j 55-9 j 55-5 56-5 55-6 55-4 55-4 j 55-9 56-5 56-5 56-5 56-4 56-3 | 56-5 ( 56-5 56-5 55-9 > 55-4 55-9 56-5 56-5 55-9 I 55-4 55-4 , 54-8 54-3 I 54-8 | 56-0 55-4 : 54-8 53-7 55-4 ' 55-9 55-4 54-8 54-3 53-1 56-1 554 ( 54-3 53-7 54-3 55-6 55-4 | 54-2 54-3 54-3 56-5 „ 25 ,. 26 ,. 27 „ 28 „ 29 .. (175 .. j 176 .. 177 .. 178 .. I 179 55-5 56-5 : 57-7 59-3 58-2 56-2 55-4 : 57-1 I 58-7 59-3 58-8 57-6 55-5 56-5 : 58-2 58-7 57-9 57-6 54-8 55-9 57-1 ! 58-2 ( 58-4 i 57-2 56-5 56-9 57-2 ' 58-2 \ 58-7 ! 59-9 ! ; .... . 55-7 : 55-6 55-4 56-5 56-4 55-9 55-9 s 55-9 55-9 57-4 j 57-6 564 57-1 | 56-7 55-9 55-4 | 55-4 54-9 55-4 55-4 55-9 55-9 55-4 55-1 55-4 54-3 53-3 55-9 55-1 54-8 54-8 55-4 55-4 55-5 | 55-4 55-5 55-4 55-4 55-5 55-9 55-4 55-2 ( 55-2 55-4 55-4 56-4 56-4 56-4 56-3 55-7 54-3 55-3 55-9 55-4 56-5 55-9 56-4 56-4 56-2 55-9 55-9 56-4 56-4 56-4 55-9 55-4 55-7 55-9 55-5 55-5 55-7 55-3 54-8 ' 544 56-0 56-5 55-9 56-5 55-4 564 56-4 554 54-3 - 54-8 i 56-1 55-9 : 55-4 55-4 j 554 56-2 55-5 ( 55-5 55-2 I 54-8 : 56-2 . _ . „ 30 .. I 180 55-1 56-5 I 58-2 58-8 58-8 | 57-5 55-8 56-9 ( 58-0 58-4 57-7 56-3 56-5 56-5 564 : I 55-5 1 55-4 55-4 55-4 55-4 55-5 55-9 56-2 56-4 56-5 56-4 56-0 56-2 56-4 56-3 56-2 55-9 55-5 55-0 55-8 | 56-3 Means 55-7 56-1 54-8 54-9 54-8 54-8 54-9 ! 55-1 [ 55-3 ■ 56-0 55-3 j 54-9 ! 55-2 : 55-9 54-9 i •■ i i ■ i i i i i i I

23

C — lA

Table of Hourly Values (Greenwich Mean Civil Time)— continued.

Magnetic Horizontal Force : 0-22000 C.G.S. -j- tabular y. Day of Month. !^°- 0f Oh. lh. Day. j *l 0 - of Oh. In. 2h. 3h. 4h. Day. j 2h. 3h. 4h. 5h. I 6h. I I I 5h. I 6h. 7h. 8h. 9h. lOh. llh. 12h. 13h. 14b. i:,h. 16h. 17h. 1 | , l_ 18h. 19h. 20h. i 21h. 22h. ' 23h. Mean. I I 1918. June 1 „ 3 .. 4 151 297 294 296 302 313 152 303 301 297 298 306 153 • 290 ( 294 : 303 309 314 154 307 ! 305 305 310 317 317 318 317 317 317 316 314 313 313 312 314 313 : 316 313 316 317 316 313 j 311 313 311 313 314 315 315 ( 317 314 316 319 321 322 319 317 316 316 315 315 316 ( 318 322 ( 319 320 322 326 320 j 321 319 322 322 322 322 | 324 318 319 321 320 319 309 313 319 321 319 322 317 297 312 318 318 321 319 317 315 314 327 327 329 329 324 319 j 320 „ 5 6 „ 7 8 „ 10 „ 11 ., 12 ,, 13 ,, 14 155 i 309 : 296 2-99 299 301 156 313 312 311 314 316 157 306 | 299 ; 304 321 315 158 310 ( 308 312 307 312 159 306 ( 306 307 : 311 316 160 307 • 305 I 282 289 302 161 264 273 : 263 266 285 162 273 262 I 248 245 243 163 266 276 j 261 281 291 164 283 278 i 279 269 271 165 291 282 , 269 282 293 166 ' 276 261 : 261 279 290 167 247 ! 275 276 286 296 168 287 289 287 291 294 169 : 300 285 i 290 297 306 170 304 298 299 305 310 171 288 '285 288 295 305 172 - 303 302 , 297 308 31.5 173 309 i 306 303 303 306 174 296 ( 291 294 304 315 309 i 312 316 316 320 318 318 314 321 321 322 325 325 320 : 319 316 j 316 321 321 316 311 313 315 315 317 ! 317 315 | 312 31.3 ; 319 321 316 309 309 316 318 318 318 ( 315 319 : 321 : 318 320 317 316 314 308 305 315 315 315 I 315 321 323 323 323 323 322 325 324 324 319 320 324 j 322 309 : 287 292 285 236 346 240 218 231 226 240 248 260 288 ! 286 285 303 287 285 281 278 305 277 286 288 293 269 ; 266 282 267 282 287 290 289 290 304 296 289 297 301 301 I 301 301 304 306 303 303 302 303 303 303 308 280 295 I 275 29] 284 : 296 : 278 : 286 298 281 301 286 288 280 299 277 262 299 292 ■ 324 ! 299 295 304 311 299 | 294 288 288 296 , 300 31.5 ' 297 293 308 303 306 303 303 i 293 291 291 293 293 304 301 301 315 303 303 301 306 : 301 296 299 ! 302 297 I 306 301 307 307 311 311 310 309 : 308 303 304 ( 304 297 ( 308 304 305 307 308 305 305 306 . 308 313 311 311 312 303 301 301 302 303 306 309 311 | 311 309 308 307 312 311 307 307 305 307 305 307 312 | 307 312 ; 306 \ 304 : 298 I 298 303 308 310 312 313 311 312 i 313 313 . 314 ( 315 : 314 315 306 309 308 311 312 312 312 I 312 318 315 '. 311 301 301 304 291 301 309 311 309 306 j 301 327 325 327 325 330 323 317 320 320 320 317 320 312 316 318 318 313 313 316 316 314 317 320 320 320 322 311 315 320 308 322 | 305 317 312 318 265 277 275 | 255 243 255 270 295 293 297 I 293 298 285 286 309 305 297 j 284 292 287 281 306 306 308 : 306 297 284 297 292 293 296 301 303 301 288 302 299 295 297 285 : 263 291 304 , 303 306 301 298 294 294 305 i 294 303 291 281 284 294 311 310 310 313 314 306 303 310 309 : 310 312 308 308 304 316 311 307 313 318 307 308 317 314 312 ( 305 305 304 305 316 315 ( 313 ! 313 316 310 309 312 312 ! 314 ! 311 312 307 310 311 311 310 | 309 306 301 305 ,, 15 „ 16 „ 17 „ 18 ., 19 „ 20 -, 21 „ 22 „ 23 „ 24 » 25 , 26 „ 27 „ 28 ,, 29 175 300 | 297 300 307 315 176 315 ! 310 309 311 311 177 273 ! 283 285 283 286 178 311 i 302 299 299 306 179 304 i 297 295 302 308 180 321 ( 309 308 308 310 .. 295 ! 293 291 296 ( 302 316 j 310 ( 312 314 314 314 310 309 314 319 319 319 I 320 308 ! 311 i 315 314 313 313 i 309 I 305 309 305 300 315 ! 319 288 297 i 298 298 | 299 298 '■■ 301 ; 304 315 310 309 310 ; 313 310 308 307 310 31.4 312 310 309 312 312 312 312 I 313 317 317 317 317 320 320 317 317 315 315 315, 317 319 315 318 317 317 317 316 : 317 316 313 313 316 316 ( 317 306 306 j 306 306 307 309 I 305 304 307 306 308 308 j 309 322 322 321 322 I 324 320 314 319 315 316 309 | 307 287 310 315 315 317 318 315 314 302 315 316 316 318 321 311 311 320 322 327 327 325 323 316 317 315 311 311 ( 311 308 314 312 311 312 309 309 302 i 305 „ 30 Means

C—U.

24

Table of Hourly Tables (Greenwich Mean Civil Time)— continued.

Magnetic Declination (east by north) : 16° -- tabular minutes. Day of Month. 1 ?°- of l Oh. I lh. ■ 2h. 3h. 4h. 5b. j 6h. 7h. 8h. 9h. lOh. | llh. 1 12h. 13h. ! 14h. 15h. 16h. I 17h. 18h. i 19h. 20h. J 21h. 22h. I 23h. [Mean, i July ■»■■ 95 55 1918. 1 2 6 4 5 6 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 Means ! I .. 181 57-1 57-1 57-1 58-2 57-6 56-5 56-5 : 56-4 ! 56-5 i 55-3 54-4 55-4 I 55-4 ! 55-9 : 56-5 56-4 ( 56-4 ■ 56-5 56-5 55-9 ; 56-5 55-9 55-4 , 55-9 56-3 .. 182 56-5 I 57-3 57-7 58-8 58-7 58-8 i 56-4 ; 56-5 56-3 55-9 55-4 55-9 i 55-9 i 56-5 56-5 j 56-5 56-5 57-1 55-9 55-9 j 55-9 554 55-4 I 54-3 56-5 .. 183 54-8 ' 57-1 58-9 59-3 58-8 574 56-5 56-5 56-4 55-4 55-4 55-4 ! 54-8 : 55-4 55-9 ( 56-5 57-1 57-1 57-1 56-7 56-5 554 54-4 . 54-3 56-0 .. 184 55-4 1 56-9 58-9 58-5 ■ 58-1 57-0 57-3 56-2 56-7 55-4 54-8 55-4 : 55-4 54-8 51-4 l 54-2 55-6 55-9 56-5 55-9 55-6 55-6 55-6 . 55-9 \ 56-0 .. 185 ( 55-7 : 55-9 57-7 58-2 57-6 57-1 , 56-2 i 56-4 56-5 i 55-3 544 55-4 56-4 : 55-9 56-5 I 56-4 I 56-4 56-5 ■ 56-5 , 55-9 '. 56-5 I 55-9 554 ( 55-7 56-3 .. 186 55-8 I 57-6 58-0 58-8 58-7 56-5 56-4 56-5 56-3 55-9 : 554 55-9 55-9 : 56-5 56-5 I 56-5 56-5 57-1 55-9 | 55-9 j 55-9 | 55-4 54-3 54-1 56-3 .. 187 55-9 58-2 58-9 59-3 58-8 57-1 56-5 56-5 56-6 55-4 : 55-4 55-4 54-8 ! 554 55-9 56-5 57-1 57-1 57-1 56-7 56-5 55-4 54-6 54-8 j 56-5 .. 188 57-1 57-1 58-2 61-0 58-8 59-1 56-5 56-5 55-3 55-4 55-4 54-3 54-3 54-8 56-5 57-1 57-6 57-6 58-2 59-1 i 57-6 54-8 54-8 55-3 I 56-7 .. 189 55-9 58-2 59-1 59-9 59-9 58-2.1 56-5 56-9 56-6(554 55-5 54-3 53-7 54-6 554 55-5 55-9 56-3 55-9 55-9 56-6 57-6 55-5 '■ 55-9 [ 56-5 .. 190 56-5 58-2 57-9 59-3 i 59-3 56-5 56-5 56-5 56-5 56-5 55-9 55-7 55-7 564 56-5 56-5 56-5 56-5 56-5 56-4 55-9 55-3 56-5 55-2 56-6 .. 191 57-1 : 57-6 58-2 59-9 j 60-0 58-8 \ 57-1 j 57-5 56-4 56-5 ; 55-4 55-4 54-3 554 56-4 ( 564 57-6 : 57-1 56-6 57-1 59-3 58-2 58-2 56-7 56-8 .. 192 57-1 j 58-2 59-9 59-3 ! 57-1 55-7 56-5 I 56-4 56-3 55-4 53-7 54-3 55-4 56-4 ( 56-5 58-9 57-1 i 57-5 57-7 , 57-1 56-5 55-4 54-8 55-4 56-6 .. 193 ' 54-8 ; 56-9 58-2 59-9 59-3 57-1 ( 58-2 | 56-4 55-9 j 55-4 54-8 55-4 j 53-1 [ 52-6 ' 55-3 56-6 574 57-1 57-1 I 56-6 56-5 55-9 54-8 ; 54-3 54-5 .. 194 55-9 58-1 59-0 59-9 | 58-8 57-1 - 56-6 56-5 55-9 I 55-7 554 55-9 I 55-9 56-5 56-5 56-6 57-1 57-1 57-1 ( 57-6 56-6 ; 54-8 53-7 ! 56-1 ; 56-7 ■ : .. 195 56-8 58-8 58-8 58-2 i 58-2 57-6 ( 53-1 i 55-5 50-9 , 54-2 \ 55-7 54-8 i 53-5 53-0 54-8 j 56-5 j 57-1 56-5 56-6 56-5 : 55-5 54-9 53-7 , 54-3 ; 55-7 .. 196 55-4 56-8 59-2 60-5 i 59-3 57-3 ( 56-5 ( 56-5 i 55-9 j 55-9 i 54-3 55-3 54-4 i 55-4 - 55-9 56-5 ! 57-1 57-1 56-5 58-2 56-7 55-9 54-8 55-0 I 56-5 .. 197 I 54-9 55-8 58-7 58-9 | 58-8 57-3 i 56-5 l 56-9 ! 56-5 | 56-5 ; 56-5 56-5 j 55-9 : 55-9 56-4 j 56-6 57-1 57-1 57-1 56-5 56-5 - 55-4 54-8 54-4 i 56-6 .. 198 54-8 56-5 I 58-4 60-5 I 60-5 59-3 ( 58-9 56-6 55-9 55-9 : 55-4 52-3 :. 54-8 55-3 56-4 \ 56-5 56-6 56-5 56-5 56-4 : 55-9 55-4 54-8 54-8 56-5 ... 199 54-8 i 55-9 I 56-5 58-2 ( 58-7 56-5 55-6 i 55-5 55-7 55-5 54-6 55-4 55-5 | 55-9 56-5 j 56-5 j 56-5 56-5 56-4 ( 55-9 \ 55-9 53-9 53-7 ( 54-3 55-8 .. 200 54-8 56-4 ! 58-2 59-8 ( 58-8 > 56-6 \ 564 : 56-5 | 55-9 55-9 ( 55-4 55-5 i 55-9 56-5 56-5 j 56-5 I 56-5 I 56-5 56-5 ( 56-5 j 55-9 55-3 53-7 i 53-7 56-3 .. 201 54-8 58-2 58-8 58-9 ! 58-7 i 57-5 56-5 ! 57-6 57-1 56-5 j 56-4 55-9 : 55-9 55-9 55-9 I 56-5 • 56-2 ! 56-2 55-9 55-9 : 55-4 54-8 54-2 \ 54-8 : 56-4 ... 202 55-9 | 58-2 59-2 59-2 < 58-2 j 56-5 56-1 ( 55-9 55-9 55-9 I 55-4 55-5 55-9 55-9 56-4 ! 55-9 ; 56-1 ( 55-9 55-4 55-5 55-4 ! 54-3 54-3 54-8 56-2 .. 203 55-9 j 56-2 57-6 58-0 j 58-5 57-6 56-6 571 57-1 56-6 i 55-9 55-4 , 53-1 : 55-4 55-9 56-6 ■ 56-7 56-5 56-5 56-3 \ 55-7 54-8 54-2 53-3 56-2 .. 204 55-5 I 57-1 58-8 59-3 i 59-3 58-8 57-1 | 54-8 56-5 56-6 55-9 55-9 I 55-9 i 56-4 56-5 : 56-6 : 56-5 \ 56-5 ! 56-5 \ 554 j 56-5 54-9 54-3 55-1 56-6 ! ( I ! i " .. 205 55-4 ; 574 57-6 59-3 59-3 59-3 ! 56-9 57-6 . 57-6 57-1 ; 57-1 55-4 ' 54-3 ( 53-3 : 52-6 j 52-6 53-1 55-9 54-3 60-5 56-5 55-4 55-4 j 54-3 56-2 .. 206 554 j 56-6 58-2 58-8 59-9 ( 59-0; 57-6 57-1 56-5 56-9 56-5 55-7 55-9 55-9 55-4' 55*9 56-5 56-2 57-1 55-9 57-1 57-1 55-4155-9 56-8 .. 207 56-3 I 57-6 60-1 59-1 I 59-0 | 58-7 57-1 j 57-1 56-5 i 56-5 i 55-9 56-5 i 54-3 54-3 55-4 554 55-4 57-1 56-5 56-5 56-5 55-7 55-4 I 55-3 : 56-6 .. 208 | 57-1 58-7 62-2 60-5 ( 59-9 I 60-3 59-9 ! 58-2 57-1 ! 55-6 j 54-3 52-6 - 51-4 52-6 ] 52-6 55-5 56-5 57-6 58-8 58-9 I 62-2 60-0 60-5 - 59-3 i 57-6 .. 209 58-5 58-4 59-3 59-3 j 62-1 ( 61-8 59-3 ! 55-4 57-6 55-8 I 55-3 52-0 : 53-1 54-4 : 53-7 55-4 55-7 55-1 59-9 57-6 i 60-0 58-2 554 ( 55-9 j 57-1 .. 210 56-3 59-3 59-9 60-7 58-8 58-2 j 57-6 49-2 57-5 56-4 55-3 52-1 54-3 54-8 54-3 : 59-8 , 56-9 55-4 554 56-6 57-5 56-5 55-4 56-5 '. 564 .. 211 56-8 58-2 59-9 61-1 58-8 57-6 j 58-3 56-5 57-6 | 54-2 : 56-4 55-5 55-4 54-1 52-0 ! 55-5 ! 55-9 ( 57-2 57-3 56-5 ; 57-6 56-4 55 9 { 55-7 56-7 .. 56-0 I 574 58-7 59-4 59-0 57-8 I 56-8 56-3 56-3 55-8 55-1 ! 55-0 54-9 55-2 55-4 56-3 56-5 : 56-7 56-7 56-7 56-7 55-8 55-1 ! 55-2 56-4 58-7

25

C—la

Table of Hourly Values (Greenwich Mean Civil Time)— continued.

4—C. Ia

Magnetic Horizontal Force : 0-22000 C.G.S. + tabular y. Day of Month. No. of ., ,. Day. 0h - lh - | 2h. I 3h. 4h. 5h. 6h. i 7h. I 8b. 9h. lOh. - llh. 12h. 13h. 14h. : I 15h. 16h. I 17h. : 18h. 19h. ! 20h. j 21h. 22h. 23h. Mean. 1918. ulv 1 ,, 2 .. 3 „ 4 .. 181 298 293 293 .. 182 297 297 299 .. 183 300 295 290 .. 184 305 288 290 ill 301 313 315 318 317 315 317 314 319 315 318 317 290 288 304 307 299 307 | 293 304 311 302 305 307 ; 313 320 313 330 317 317 314 309 312 300 304 302 308 305 310 307 286 290 307 309 310 310 309 : 307 306 307 : 310 j 310 278 ! 285 ! 291 ! 310 207 307 309 297 291 300 307 312 312 311 306 303 316 305 310 ( 305 ... ._._._... i ... i __ 308 I 310 308 308 : 313 313 315 315 309 307 i 312 314 317 ( 314 312 j 302 302 311 308 308 311 311 I 311 310 316 311 305 302 , 300 305 310 ! 310 310 I 315 312 305 309 I 310 310 ! 310 j 315 312 | 315 310 ; 306 310 I 305 307 ( 312 315 315 312 297 308 309 [ 310 315 317 I 324 330 337 334 ( 311 307 310 315 320 I 307 300 302 293 ( 301 305 310 ( 315 I 317 j 310 290 303 ] 296 j 302 316 : 318 322 323 318 313 : 289 I 288 306 307 i 304 302 303 299 297 297 292 293 308 i 308 30S 313 320 308 I 308 293 i 298 302 j 311 312 313 315 312 j 307 299 304 309 ( 314 318 319 326 324 I 290 297 | 307 304 301 304 304 309 305 301 292 ■, 300 312 240 340 321 322 320 ' 317 306 ! 308 315 317 317 ; 322 329 332 329 329 ( 314 308 ! 311 313 | 312 315 317 317 315 I 304 309 I 309 309 309 314 315 ! 311 301 ! 307 I 300 305 307 310 I 307 302 j 297 305 312 307 310 307 : 300 I 307 307 : 312 314 309 295 ' 283 290 297 288 287 298 306 303 303 301 301 294 292 301 311 313 311 292 - 290 277 287 287 295 284 288 I 303 303 : 305 308 287 299 304 307 309 310 296 | 305 313 312 \ 310 311 i I ., 5 „ 6 -.- 8 » 9 .. | 185 I 310 : 301 ; 295 .. I 186 306 2-97 295 .. 187 291 290 295 .. | 188 326 : 315 302 .. | 189 286 281 289 310 310 : 307 310 ! 315 314 311 j 310 309 302 j 305 305 304 307 , 308 „ 10 » 11 ,, 12 ,, 13 „ 14 „ 15 „ 16 „ 17 „ 18 » 19 .. 190 282 ' 286 284 .. 191 268 270 282 .. 192 262 I 266 271 .. 193 285 290 282 .. 194 291 ( 291 289 .. 195 298 295 285 .. 196 273 , 283 274 .. 197 297 297 295 .. 198 322 311 296 .. 199 304 : 296 [ 290 i 314 313 313 309 299 294 - 295 290 305 305 ( 285 300 310 312 316 319 310 309 I 308 308 343 I 314 317 297 ( 299 300 303 ! 308 286 307 [ 292 307 307 309 309 300 298 304 307 307 308 314 312 : 312 311 ! 306 i 306 307 311 308 293 298 ; 295 ( 303 298 289 291 297 303 305 310 307 300 310 314 ! 315 312 312 284 294 298 291 288 285 294 305 309 309 309 311 2S3 312 310 ( 315 321 317 314 299 315 315 315 307 297 297 309 302 309 311 311 305 „ 20 „ 21 „ 22 „ 23 „ 24 „ 25 „ 26 ;, 27 „ 28 „ 29 .. 200 292 290 292 .. 201 296 299 I 304 .. 202 294 , 294 ( 294 .. I 203 297 ( 297 | 297 .. | 204 | 297 ! 297 \ 297 .. | 205 298 ( 298 295 I .. I 206 285 : 283 285 .. (207 280 280 274 .. j 208 269 286 276 .. I 209 254 j 245 263 305 314 317 316 315 310 j 307 313 313 l 311 311 309 301 313 316 ! 313 313 311 ( 299 309 317 317 314 309 I ( 297 307 309 307 306 i 312 I i | 296 310 322 323 303 303 ( 285 285 278 j 285 298 j 300 < 275 284 296 j 289 295 295 274 282 283 282 286 293 275 265 254 269 277 283 ( 313 313 315 318 309 311 311 311 308 308 ' 308 313 : 295 309 312 317 314 314 314 312 305 297 j 301 302 1 300 293 298 298 293 293 285 283 | 288 288 I 296 306 i 287 287 285 282 ...-._... 319 ( 320 319 311 ( 310 310 314 I 313 311 304 307 312 309 | 309 309 306 302 292 298 ( 295 293 291 ( 284 286 303 296 299 286 311 289 320 321 322 i 322 325 322 ( 321 310 314 310 310 310 ! 312 314 314 j 314 307 \ 309 313 308 313 313 318 313 | 312 325 : 310 312 313 314 315 324 322 j 322 312 ( 310 314 314 317 317 317 3*18 ! 314 314 310 294 287 294 316 292 294 302 292 ; 301 303 i 298 290 ( 300 298 300 293 285 ( 295 289 289 295 '■ 295 297 299 300 292 289 300 305 319 i 314 283 265 \ 238 246 287 289 289 309 ( 301 291 289 : 284 283 281 287 286 289 291 290 286 i 285 275 282 296 294 293 294 288 291 I 306 297 290 306 307 310 311 310 308 I 306 301 302 I „ 30 „ 31 i .. 210 281 | 265 267 .. 211 277 \ 277 275 I Means .. 291 i 289 288 281 280 298 273 ( 257 273 280 279 290 274 291 293 293 298 302 302 302 303 278 278 j 279 283 291 299 293 292 282 286 313 294 296 294 303 304 305 305 304 304 305 306 305 307 310

C.—li.

Table of Hourly Values (Greenwich Mean Civil Time)— continued.

26

Magnetic Declination (east of north) : 16° + tabular minutes. Day of Month. f 0h - lh - 2h - 3h - 4h - 5h - ' 6h - 7h - | 8h - 9h - 10h - I llh - I 12h - 13h - I 14h - 15h - 16h - 17h - 18h - I 19h - 20]l - 21h - 22h - 23h - Mean - ll. I I 1 I I I 1918. August 1 2 3 I 212 56-4 58-1 60-5 60-9 I 60-1 58-5 56-5 56-9 57-1 213 55-7 56-9 58-8 60-0 59-8 58-8 57-1 57-1- 574 214 57-9 58-8 60-0 57-5 58-8 57-1 56-5 56-9 55-9 55-9 55-5 55-9 55-4 55-9 55-9 '__.___-.. 55-5 I 55-4 i 55-3 54-1 ( 55-4 \ 55-7 56-5 57-5 j 52-1 ! 55-3 55-9 56-4 54-1 57-5 56-4 55-9 55-9 57-6 56-7 57-6 55-5 55-9 j 56-5 56-3 I 56-5 54-8 56-5 : 564 56-5 j 59-9 57-6 57-4 57-6 57-6 j 56-5 554 57-1 56-5 56-9 i 57-7 57-1 56-5 56-6 56-5 j 56-5 | 56-5 56-5 : 56-4 55-9 | 53-9 j 54-3 56-5 : 57-1 57-6 I 61-6 I 55-4 57-6 | 57-6 57-4 56-5 | 54-8 I 54-2 57-6 54-3 54-8 56-9 53-1 56-6 57-2 56-5 4 5 7 8 215 53-7 56-5 58-9 ! 58-8 : 58-8 57-5 56-9 57-0 [ 56-6 216 53-9 56-7 58-8 | 59-9 '• 59-8 58-8 57-1 57-5 | 56-7 217 57-6 60-0 60-7 61-0 j 60-9 58-9 57-6 56-5 55-4 218 57-6 58-6 I 59-8 59-8 j 59-3 57-1 55-9 57-5 514 219 53-7 55-4 j 58-7 59-0 i 58-2 58-2 53-1 54-8 55-7 56-6 55-3 56-5 564 52-0 54-8 56-2 55-6 56-5 57-1 55-1 55-4 55-3 54-8 55-7 I 55-3 53-1 564 55-9 j 55-9 55-9 55-9 53-1 I 51-7 54-3 55-9 57-5 52-1 53-7 56-5 54-8 56-4 55-9 55-9 56-5 55-4 56-5 56-9 55-9 56-9 56-5 56-5 57-1 58-7 60-5 54-4 54-9 53-8 54-1 54-2 53-1 55-9 54-3 53-2 55-5 56-3 56-6 56-6 56-4 564 9 10 11 12 13 220 54-7 58-0 59-9 60-5 59-3 57-6 54-8 i 52-5 54-3 221 56-5 57-1 58-8 59-9 59-3 57-3 56-5 j 56-6 56-4 222 53-7 56-1 58-9 57-6 59-3 58-2 56-6 56-9 53-7 223 54-8 55-4 57-3 58-8 55-4 56-4 55-3 53-1 56-6 224 54-4 57-1 59-1 60-0 59-8 57-6 55-9 56-6 55-8 54-6 55-4 56-4 55-5 51-4 554 564 554 55-4 ( 55-5 i 55-4 | 55-4 55-6 55-6 - 55-4 i 55-5 56-5 I 56-5 554 55-9 53-1 ( 52-0 52-2 54-3 55-3 I 55-9 55-5 55-5 59-3 i 55-9 - 55-6 56-5 52-0 55-9 55-9 56-2 I 59-3 56-6 56-6 55-3 55-5 55-9 56-5 56-5 57-1 58-8 i 57-5 58-2 I 57-0 55-4 57-1 56-5 56-5 | 55-3 | 54-3 56-5 57-5 58-2 : 57-1 55-4 56-6 56-5 56-5 ! 55-5 53-5 57-6 56-5 56-5 ( 55-5 ; 54-8 56-6 53-1 54-3 52-0 54-7 55-7 52-5 54-4 52-6 54-3 56-6 56-3 55-7 55-3 56-5 „ 14 ,, 15 16 .. 17 18 225 55-8 57-6 60-7 60-8 i 59-7 58-5 56-5 57-1 57-1 226 54-8 56-5 60-2 60-5 I 59-9 58-3 j 56-5 56-9 56-5 227 56-0 57-0 59-9 62-1 j 58-7 58-9 59-4 55-9 57-0 228 54-8 57-1 58-8 59-8! 59-9 58-3 56-6 57-1 56-4 229 54-0 58-2 59-8 59-9 1 59-9 58-8 57-5 i 57-5 57-1 56-9 | 53-1 56-5 I 56-5 52-0 ! 45-9 56-5 i 55-9 56-5 i 56-4 55-9 53-1 | 54-4 55-9 564 56-4 564 56-5 46-5 48-5 51-4 53-9 55-9 56-5 56-5 56-5 | 56-5 56-5 56-5 I 56-5 55-9 56-5 53-9 56-5 56-5 56-3 55-9 j 56-9 58-9 | 54-8 55-9 I 56-5 56-5 56-6 57-1 58-7 56-9 ( 56-4 : 55-4 ( 54-8 59-3 58-2 ( 57-6 56-5 59-9 57-1 56-9 56-5 54-8 53-1 56-5 56-5 56-4 55-1 53-1 57-0 56-5 56-3 54-5 51-6 | 56-6 56-5 1 55-9 54-8 53-1 55-9 55-9 ! 55-9 55-4 53-5 j 55-9 56-1 55-4 ( 54-8 53-1 56-3 55-8 55-2 57-4 i 53-5 I 58-2 56-6 55-9 j 55-4 ( 54-3 53-3 55-5 52-6 52-0 514 53-7 55-9 53-1 52-0 51-9 56-4 57-4 54-9 56-3 56-4 ,, 19 ,, 20 21 „■ 22 „ 23 230 54-1 57-0 58-9 I 60-0 59-9 58-7 56-6 56-7 I 56-5 231 54-8 58-2 59-3 j 59-8 53-1 59-8 58-8 58-8 56-5 232 57-6 594 61-6 62-7 62-3 59-3 56-7 56-6 56-5 233 54-3 57-2 58-8 60-8 61-2 59-4 58-2 59-1 58-2 234 55-3 58-2 [ 60-7 61-6 62-2 59-8 J 57-6 57-1 57-1 235 55-7 58-3 58-8 59-8 60-2 59-3 58-8 ! 56-5 58-2 236 57-2 58-8 j 61-6 62-7 62-2 61-0 58-8 I 58-8 574 237 54-6 i 57-7 : 61-1 61-0 i 63-3 ! 61-0 ; 61-6 ; 58-8 50-9 238 55-9 58-5 j 59-2 62-2 57-6 : 57-6 j 58-8 ( 54-8 : 57-1 239 55-9 | 58-1 I 59-3 60-5 59-6 i 58-2 i 57-1 I 57-1 57-1 240 56-2 58-4 60-9 60-5 59-3 58-3 i 57-6 57-6 57-6 241 56-4 57-6 59-8 1 59-9 59-2 58-2 1 57-6 57-6 57-9 242 55-6 58-2 59-3 1 60-2 59-6 58-8 57-6 57-5 57-1 .. 55-5 57-6 59-6 60-3 1 59-6 58-5 57-2 56-8 56-3 56-5 56-5 56-6 56-5 ( 544 54.8 54-3 55-4 56-6 56-5 i 56-5 | 56-4 55-7 j 55-9 54-7 56-1 54-3 | 55-5 55-8 56-5 56-5 55-4 56-4 56-1 56-5 56-5 56-6 ( 56-5 56-5 ( 56-5 56-3 j 56-3 56-1 57-1 56-3 j 52-8 53-1 52-6 52-9 53-5 - 56-4 56-1 56-9 56-6 56-9 56-6 ( 56-6 57-1 I 55-1 56-5 j 56-5 57-1 | 55-9 57-1 55-1 53-1 54-4 52-7 53-1 I 54-4 „ 24 „ 25 „ 26 „ 27 28 | 52-8 : 54-4 56-5 ; 53-7 57-5 ' 57-6 55-9 57-6 55-8 53-1 I 53-7 52-8 52-6 54-4 49-2 46-4 55-4 53-3 59-3 54-3 53-7 54-3 514 48-1 ( 58-8 54-8 I 55-3 53-7 | 52-2 55-9 54-4 53-3 54-3 54-8 55-9 55-9 55-9 55-4 54-8 54-3 59-9 j 54-5 56-5 j 56-5 56-5 | 53-3 ( 55-4 54-6 I 54-9 54-3 i 55-4 ; 56-6 55-9 | 55-1 53-1 I i 57-1 ( 56-5 56-5 ( 554 53-3 ( I 554 56-5 57-0 : 56-5 .55-3 i 57-1 56-5 55-9 554 54-2 1 55-5 52-6 53-1 54-4 54-4 554 52-6 53-7 55-1 54-8 55-9 56-0 56-9 56-6 56-3 ,, 29 „ 30 „ 31 57-1 54-8 57-6 56-5 56-5 54-7 I 54-3 55-4 56-5 56-5 i 54-8 55-4 56-5 55-9 ( 55-9 56-1 56-5 56-6 56-5 55-9 56-6 56-5 : 57-1 554 ( 56-5 56-6 I 57-4 56-5 56-5 55-9 j 55-3 54-3 56-5 55-9 56-5 i 54-8 53-7 55-4 55-6 j 60-5 j 58-1 58-8 54-3 53-1 58-2 54-3 54-0 54-3 56-7 56-6 57-3 ! I I l ' i 1 . I. I Means 56-3 55-9 ( 55-2 I 54-7 54-4 55-3 55-7 56-3 i 56-8 56-7 ( 56-6 I 56-6 564 54-7 54-0 54-4 56-7 54-0 564 1 I I I I I

27

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Table of Hourly Values (Greenwich Mean Civil Time)— continued.

agne' no onzonta orce : ar y. Day of Month. No. of Day. Oh. lh. 2b. : 3h. 4h. 5h. 6h. I 7h. 8b. ! 9h. I lOh. i 1 i i llh. \ -12h. 13b. I i [ I I , I i ■ I I 14h. ( 15h. i 16h. 17b. , 18h. ISh. 20h. 21h. ( 22h. j 23h. Mean. : I i I i I 1918. August- 1 2 3 4 5 6 7 8 .. 212 .. 213 .. 214 .. 215 .. 216 .. 217 .. 218 .. 219 286 276 , 282 288 293 296 297 293 279 279 291 300 304 316 270 256 264 256 266 j 263 281 I 298 j 298 302 ' 304 296 : 272 285 ; 290 299 ( 299 303 : 296 301 298 295 ! 300 299 I 307 ! i 302 305 306 j I 301 293 296 j 305 308 313 306 306 305 306 i 303 302 306 I 306 309 293 '' 296 298 : J 309 ( 309 309 304 I I 305 ( 300 290 285 '' ' 303 [ 300 301 288 I 299 297 289 288 290 283 287 290 297 302 290 286 291 292 301 304 307 291 283 276 283 286 291 305 279 276 283 288 300 312 307 267 282 287 287 294 298 287 301 312 ( 303 ! 308 315 300 300 319 301 334 298 298 299 323 290 290 i 290 299 297 297 309 302 300 304 304 308 I 303 I 303 : 308 303 ! i 302 304 298 302 296 I 266 259 271 281 305 313 I 305 288 267 274 287 310 307 I 310 289 273 282 271 294 304 309 298 284 295 298 304 302 286 298 292 291 298 307 309 310 I I 303 303 299 302 288 312 314 314 293 302 308 I 300 300 303 314 ! 305 306 279 316 I 309 315 303 323 302 313 j 313 315 318 309 300 309 297 300 ! 302 306 310 310 | 308 . 320 309 i i 310 313 302 328 312 315 307 307 313 311 311 324 307 ( 320 313 302 303 310 308 313 304 313 296 307 308 301 313 305 309 308 i I 308 308 315 I 302 312 307 : ! 303 305 308 I 310 313 323 ( 304 304 297 I 302 312 304 ' 315 316 318 305 307 320 I 312 314 317 313 312 313 317 300 : 320 308 311 304 j 304 296 I 312 303 ' 296 288 ( 325 315 306 296 309 306 291 265 296 207 302 306 307 9 „ io 11 ,, 12 „ 13 14 15 16 17 „ 18 .. 220 .. 221 .. 222 .. 223 .. 224 .. 225 .. 226 .. 227 .. 228 .. 229 295 281 286 294 310 315 317 266 272 278 283 293 304 301 260 254 258 238 246 280 282 261 264 269 273 281 285 283 276 276 268 269 283 295 298 292 | 280 283 292 305 312 311 294 ( 287 295 297 ' 314 314 ! 307 267 ( 263 272 282 302 311 j 314 293 : 288 294 301 305 313 ! 314 281 ( 276 279 | 284 302 308 ( 313 304 292 296 307 | 311 316 309 259 263 263 273 ! 256 283 289 280 272 265 269 270 274 285 ( 287 287 281 | 292 ' 287 I 289 295 276 269 282 j 289 297 ( 306 307 295 i 284 287 I 289 299 307 308 295 288 292 , 298 ] 308 308 312 308 299 299 '-. 305 307 313 311 284 277 281 ( 288 : 294 301 i 302 i i i 322 321 315 320 312 318 318 320 297 285 260 242 292 294 299 299 300 295 300 301 I 315 313 305 ( 320 313 I 313 [ 225 287 267 294 296 | 298 303 304 304 308 315 265 299 305 308 342 268 299 305 308 313 307 371 323 ( 325 273 277 281 299 301 304 305 307 ! 310 I I 310 307 j 275 297 321 311 I 305 304 309 315 303 298 318 317 311 ! 304 314 310 293 | 293 415 303 284 271 288 295 290 290 285 285 281 272 306 301 294 283 312 307 j 307 | 302 316 318 ' 311 ! 301 305 298 ( 292 281 316 309 : 304 302 317 310 I 298 285 315 313 : 313 308 305 307 268 290 297 311 318 j : 263 [ j 297 304 19 „ 20 „ 21 „ 22 23 .. 230 .. 231 .. 232 .. 233 .. 234 313 313 315 315 302 307 297 307 289 309 ( 316 314 308 305 310 311 315 313 314 321 i 314 298 309 310 319 312 310 310 298 301 293 309 309 309 310 310 311 309 308 312 311 299 309 314 313 311 298 309 314 313 311 313 316 | 298 299 299 ( 309 309 309 | 314 314 315 315 313 313 308 299 302 311 307 „ 24 „ 25 ,. 26 „ 27 28 .. j 235 I .. i 236 1 .. j 237 I .. | 238 ( .. I 239 311 287 285 288 292 251 260 275 277 319 289 295 329 289 287 310 310 309 310 309 310 275 326 304 307 299 I 298 301 297 271 271 299 294 294 270 270 299 307 309 295 299 274 302 282 297 310 299 285 I 287 ( 299 ( 315 313 310 291 293 295 I 294 299 299 | 285 287 295 302 304 305 I 308 286 271 261 301 296 293 : 288 304 331 302 289 295 295 292 287 305 329 299 ! 302 299 278 292 291 301 [ 309 310 307 - 304 322 319 320 i 317 340 327 321 i 311 310 307 299 j 293 ,. 29 30 ,. 31 Means .. 240 .. 241 .. , 242 311 304 ( 311 310 311 310 ; 312 306 315 317 305 313 307 312 311 299 304 305 308 310 315 311 314 316 302 302 303 304 311 316 306 308 331 307 305 : 309 307 310 315 331 328 ( 314 303 309 315 : I 304 304 301 304 ■ 303 301 303 ': 306 303 305 307 307 308 307 300

C—la.

Table of Hourly Values (Greenwich Mean Civil Time)— continued.

28

Magnetic Decimation (east of north): 16° + tabular minutes. Day of Month. In- f i I ( p a Oh. lh. 2h. 3h. 4h. 5h. 6h. 7h. j 8h. 9h. lOh. llh. 12b. ! 13h. 14h. lob. 16h. ' 17h. j 18h. 19h. 20h. I 21h. 22h. ' 23h. Mean. 1918. September 1 2 3 4 5 6 » 7 8 9 10 11 12 I I - 243 57-1 62-7 i 62-7 ! 62-7 244 56-9 59-4 i 59-3 '■■ 59-9 245 56-0 | 57-0 I 57-5 58-8 246 54-1 ! 57-1 ' 59-3 60-7 247 56-0 ; 58-2 : 59-8 ( 61-1 : 248 54-6 I 56-9 | 58-8 ! 60-5 i 249 55-8 ( 57-6 j 58-8 ( 61-6 ! 250 ! 54-3 58-2 58-9 60-5 251 ! 56-1 58-2 57-6 59-0 252 ' 55-7 57-6 59-2 60-0 253 55-4 57-5 58-8 60-2 254 j 53-7 55-9 57-6 58-8 ... _ 61-5 i 58-8 58-8 57-6 58-8 j 57-1 60-5 ! 56-5 60-5 58-8 59-3 58-0 60-0 | 58-9 62-2 58-8 59-3 58-2 60-2 58-8 59-9 58-8 58-8 58-8 i 58-1 57-2 50-3 ( 47-9 52-0 50-9 52-8 , 57-1 57-1 ! 60-0 56-7 j 56-6 56-6 | 49-9 55-9 ; 554 56-2 56-5 ( 56-6 58-9 57-1 57-1 j 55-3 52-0 55-4 54-8 56-5 53-7 55-4 j 55-9 j 56-5 j 57-6 61-0 I 51-4 57-2 57-1 56-5 55-4 ( 49-2 47-0 ! 58-2 j 56-5 I 56-4 ' 58-2 55-4 j 54-4 56-3 , 59-9 j 54-3 j 52-0 ] 56-5 ! 56-5 57-1 \ 62-2 59-9 56-5 56-5 53-7 ! 55-4 ( 55-4 | 55-3 i 56-5 ( 55-4 - 55-9 58-2 60-9 57-6 56-5 ( 56-5 ; 53-1 ( 53-7 56-5 53-1 | 554 j 56-3 57-1 57-6 ! 57-6 57-1 55-8 | 49-5 53-1 55-1 '■ 57-6 ( 56-6 57-5 I 56-5 58-8 j 1 56-4 52-6 56-5 ! 57-1 ! 57-1 56-6 56-5 ! 57-1 57-1 57-6 57-1 I j 57-1 57-1 57-6 : 57-3 57-1 56-5 55-8 56-5 56-5 56-6 56-5 I I 57-1 57-1 I 57-0 ( 57-1 56-7 564 56-5 55-8 \ 56-4 56-5 I 56-6 ( 57-7 58-2 ( 57-6 j 57-6 57-1 57-1 56-5 56-5 j 56-5 574 j 56-5 58-3 58-2 58-2 57-6 56-5 55-9 55-8 52-0 1 52-8 53-8 57-5 58-2 58-1 58-2 I 59-3 54-1 53-7 52-0 53-1 ( 53-7 54-3 55-3 57-6 57-6 57-6 ' 57-6 I 56-7 554 j 55-2 56-5 [ 56-5 i 57-1 56-6 58-7 57-6 57-6 56-6 i 56-5 55-9 55-9 55-5 ' 55-9 55-4 55-2 ( 59-3 59-1 57-6 : 57-1 ( 53-7 50-3 ] 49-4 52-0 54-8 • 58-0 56-5 57-3 j 57-6 I 59-9 1 57-6 59-9] 58-7] 58-8! 58-8 1 57-1 56-5 56-5 57-1 58-8 57-1 56-5: 56-5 58-8 58-2 57-3 1 56-6 57-1 56-5 57-2 56-5 59-3 1 57-6 54-9 52-0 54-3 56-7 56-5 j 54-8 53-1 52-2 53-7 56-4 55-7 55-4 54-4 j 53-1 52-0 56-1 55-6 : 55-3 54-3 53-3 53-6 55-7 57-5 ( 55-9 54-2 53-1 53-1 57-2 57-6 1 554 53-1 52-6 53-1 56-6 57-6 55-9 52-6 50-9 1 51-4 56-3 58-2 58-2 54-3 53-7 | 53-3 56-7 57-3 ( 55-9 544 52-0 | 53-7 56-6 55-9 i 55-1 53-5 | 53-7 53-1 56-7 56-3 54-8 53-7 ; 52-6 53-1 56-6 55-9 54-3 53-1 52-6 53-1 ( 56-4 13 14 15 16 17 255 j 55-0 56-9 58-8 60-5 256 i 54-8 57-2 58-9 60-1 : 257 53-8 57-6 59-9 61-6 258 ! 55-9 59-3 I 62-7 64-4 l 259 I 57-1 57-1 j 60-0 614 ( 60-9 59-3 60-0 58-8 61-0 58-8 62-5 60-5 j 63-3 57-1 56-5 56-5 56-5 54-8 56-4 56-5 56-5 56-5 56-5 57-5 55-5 53-7 j 52-0 51-6 53-1 56-1 56-5 I 55-4 54-0 52-5 52-4 56-0 56-5 I 54-3 : 52-0 ( 51-0 52-4 56-5 55-4 ! 53-7 ( 514 > 51-0 52-0 56-7 56-3 ! 54-8 : 53-7 52-9 j 53-1 56-2 18 19 20 21 22 260 . 54-8 56-5 , 58-9 j 60-0 I 261 ; 55-1 57-6 I 61-6 I 644 262 j 57-7 61-3 j 63-3 ] 65-6 263 I 58-2 58-2 | 59-4 : 62-7 264 57-2 58-8 i 60-5 j 62-2 ' 59-9 60-5 65-0 63-8 : 59-8 59-9 60-5 62-5 60-9 61-0 58-3 56-5 54-4 ; 56-5 j 53-7 55-4 56-5 : 55-4 I 55-4 54-6 56-3 58-8 i 58-8 58-2 ! 53-1 ' 50-8 54-4 57-1 56-9 ! 53-7 , 57-1 56-2 54-5 ! 56-5 56-6 ( 55-9 j 53-1 51-0 52-6 52-0 I 55-9 ( 554 59-3 61-5 I 54-8 40-2 ' 46-5 44-1 46-4 41-3 45-8 I b£-l 52-1 58-2 I 59-9 j 57-6 57-6 j 57-5 j 56-9 56-9 564 554 ( 57-1 : 57-1 57-6 564 57-6 57-6 54-8! 58-0 i 56-5 57-7 56-9 55-4 60-5 55-5 | 53-7 52-3 \ 52-2 53-1 56-0 55-5 ( 554 52-6 i 53-7 55-4 57-1 56-2 54-3 ; 52-2 50-6 53-1 56-3 56-5 55-4 '< 53-7 ! 55-9 58-2 53-4 57-1 : 53-0 52-6 51-4 : 52-6 57-3 I I 23 24 25 26 27 265 54-8 58-2 | 61-0 ( 62-7 266 ( 55-8 59-1 61-5 ' 62-6 267 55-9 59-3 j 61-6 62-6 268 ' 58-8 58-8 : 60-5 61-0 269 54-8 57-6 : 60-1 62-7 63-7 i 62-7 61-2 61-0 62-2 61-0 60-9 60-5 63-3 | 62-1 I 59-3 ( 58-7 57-6 57-6 : 56-6 ! 56-5 ! 56-5 '< 56-6 56-5 58-8 57-6 I : 59-3 56-3 54-3 I 55-7 ' ! 54-8 51-1 j 52-0 j 55-4 55-6 55-4 59-9 j 58-2 58-9 55-9 j 57-1 i 56-5 | 55-9 ( 55-9 j 54-8 56-5 ! 55-4 55-4 | ! 59-0 58-2 57-1 I 57-6 57-1 | 56-5 j 56-5 55-5 55-9 ( 56-5 56-7 | 59-9 58-9 57-5 : 57-5 i 56-5 | 55-7 54-2 i 53-7 54-3 54-3 57-6 59-8 58-2 57-6 56-6 I 54-8 j 55-4: 55-9 53-1 51-4 54-5 59-3 58-2 57-1 57-1 55-5 j 54-8 55-4 j 56-5 55-9 56-5 j 56-5 57-1 . 55-5 55-4 55-9 53-1 53-1 56-7! 54-5 56-5 59-3 57-5 57-6 I 57-7 I 57-0 55-8 55-7 54-8 j 54-5 54-5 55-1 55-4 i 56-6 57-6 57-6 56-5 56-4 56-4 56-5 57-7 56-5 55-4 57-6 55-9 55-5 53-3 50-9 I 50-5 i 53-0 ' 57-2 54-8 55-4 52-0 i 52-6 53-7 56-4 54-3 52-6 j 50-9 51-9 54-8 ( 56-6 55-5 53-1 51-1 52-0 53-4 56-9 I 54-3 53-1 51-4 52-6 54-3 56-6 28 29 30 270 55-7 58-2 ; 59-3 | 60-0 271 56-5 58-8 | 59-4 . 61-0 272 57-1 58-5 59-9 ( 61-1 : ! .. 55-8 58-2 ! 59-9 61-3 I 61-0 60-9 60-5 58-8 59-9 57-6 58-8 57-1 61-0 60-5 58-8 55-9 I 57-6 I 54-3 51-4 52-6 , 53-7 56-7 57-1 54-8 52-7 53-7 ( 52-7 56-8 54-3 52-9 51-4 53-1 55-1 56-4 56-2 54-7 52-8 52-5 ; 53-5 56-4 Means 1 : i 55-8 i 60-9 59-5 57-4 57-2 1 I I , , ,

29

C—la

Table of Hourly Values (Greenwich Mean Civil Time)— continued.

Magnetic Horizontal Force : 0-22000 C.G.S. + tabular y. Day of Month. 15ay f 0h - I lh - 2h - 3h - 4h - 5h - I to- 7h - 8h - ( 9h - 10h - Ill I i llh. : 12h. : 13h. | 14h. 15h. ] 16h. 17h. j 18h. 19h. ! 20h. ! 21h. 22b. 23b. iMean. ' I I | | I i 1918. September 1 ,; 2 3 4 5 6 „ 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 .. 243 I 288 ( 261 | 268 .. 244 : 263 : 273 | 284 J .. 245 277 ; 282 272 .. 246 - 275 i 260 I 269 .. 247 267 251 \ 275 I .. 248 269 293 298 \ .. 249 273 293 293 j .. 250 285 267 279 .. 251 278 276 ! 273 .. 252 284 281 I 284 .. 253 290 282 i 278 .. 254 303 298 ! 296 .. 255 322 I 313 312 .. 256 298 ' 292 289 .. 257 286 j 281 280 .. 258 279 I 288 286 .. 259 I 264 : 264 271 .. 260 ; 278 : 288 293 .. 261 ! 293 290 300 .. 262 \ 261 : 254 288 ( .. 263 ' 272 ( 263 272 .. 264 i 243 ( 254 259 I [ I I I " I I I "" ' ■ | I - I" 278 ! 286 293 j 283 300 267 | 306 \ 287 - 285 I 284 292 309 293 299 308 ( 298 291 306 ; 296 267 291 289 292 300 , 302 I 305 302 295 307 : 308 307 i 310 308 309 308 311 308 311 316 ( 318 ( 315 311 306 303 296 304 285 : 285 : 282 299 326 302 338 j 311 314 315 305 330 315 306 310 ( 305 298 293 288 302 274 292 ; 296 301 296 292 j 318 326 309 294 , 308 299 302 302 304 304 303 ( 299 287 282 267 294 294 306 309 301 I 300 301 323 330 308 311 i 306 303 304 297 302 312 297 309 304 297 297 300 300 I 299 309 : 314 ( 314 307 j 308 ( 342 328 328 > 320 312 312 327 322 301 316 313 311 298 278 309 293 i 302 315 313 ; 317 311 | 322 j 313 317 313 ( 308 : 310 306 305 303 313 313 313 327 310 302 308 297 280 : 284 : 298 305 , 296 350 ! 286 | 295 i 308 302 302 310 310 308 ! 311 i 296 309 296 294 284 298 293 305 308 : 308 325 ' 317 317 ; 312 ] 319 ' 320 310 312 317 315 320 322 I 324 ! 321 | 315 301 i 289 308 299 309 , 309 ( 313 , 313 313 I 318 315 313 i 314 : 311 313 316 316 318 321 | 319 322 313 299 j 294 309 289 305 i 312 ' 315 320 320 : 319 319 ; 318 : 317 317 ' 317 314 314 319 322 322 324 319 313 ! 304 311 296 304 ! 308 313 313 316 319 319 313 318 : 315 319 319 319 323 324 326 329 329 331 : 331 316 309 311 313 313 315 304 310 '310 310 311 j 300 300 295 317 ( 325 305 308 i 306 308 305 303 , 309 297 306 ! 309 321 320 321 321 ( 321 : 296 : 297 ( 304 306 301 316 ; 301 306 304 310 311 310 292 307 283 291 296 305 ' 307 304 : 301 ! 300 305 I 310 307 312 313 311 ( 310 318 319 I 319 306 292 I 287 ' 302 292 288 -' 300 - 307 ( 308 309 315 I 316 322 i 320 ! 314 313 313 315 328 '. 316 311 ; 311 297 ' 280 ! 278 304 288 295 ( 286 294 : 294 303 309 ( 307 | 302 ( 282 295 289 286 323 ' 294 287 293 : 291 284 277 277 290 303 308 297 275 241 238 260 294 I 286 283 308 293 295 293 295 : 296 296 i 294 : 284 290 286 286 278 266 303 290 278 260 264 293 j 292 ( 295 291 280 315 286 '. 286 ' 286 286 ( 288 l 268 278 273 287 292 298 I 285 283 282 283 : 295 269 ! 277 ! 280 288 280 287 283 , 293 I 289 289 ! 291 286 270 274 283 281 272 I 280 280 292 272 j 258 243 ' 223 ' 204 270 228 231 263 272 279 260 i 243 236 214 232 256 242 256 261 : 260 278 278 ( 278 276 278 ( 281 281 281 308 311 286 266 ( 271 i 288 273 269 261 272 251 271 271 I 273 ! 273 : 289 I 287 290 . 289 291 ( 290 289 ( 290 299 295 • 289 290 ; 287 280 : 268 263 278 279 288 302 ; 291 298 i 267 I 294 316 \ 296 298 - 294 - 290 ( 293 311 290 284 289 i 283 280 271 268 2-86 277 291 303 291 287 314 j 295 292 299 299 ! 302 > 319 : 304 295 296 299 : 297 ! 297 295 j 285 280 292 292 299 304 305 308 309 ! 309 310 308 307 304 307 I 304 304 309 310 319 : 317 311 S 302 292 303 294 301 302 j 298 301 295 295 301 306 307 304 304 299 287 | 305 305 i 305 ( 298 288 j 283 279 296 289 297 • 260 j 310 ., 310 311 295 307 i 302 320 i 302 302 302 318 i 312 325 316 I 299 301 279 272 299 300 312 ; 307 ( 307 296 297 | 297 297 I 305 304 ! 302 ! 305 305 308 ( 315 313 318 I 301 290 ■ 275 274 299 272 293 319 309 304 ; 294 326 322 ( 328 303 311 j 322 312 298 ( 288 307 305 I 295 280 , 264 261 ( 295 287 295 | 298 ( 299 299 I 296 ! 305 ! 303 I 302 '■ 301 303 i 301 302 ( 306 ( 305 ] 304 j 304 I 303 296 ( 287 , 283 l 296 I I I | I. I | I I - I I i I ! I i I 23 24 25 26 27 .. 265 ( 257 247 237 .. 266 I 254 257 264 .. 267 263 263 268 ... 268 - 280 277 282 .. 269 281 l 276 281 I 28 29 30 Means i .. 270 277 282 284 .. 271 260 277 288 .. 272 ( 262 245 262 ( .. i 276 274 I 280 I I I 274

a—la.

Table of Hourly Values (Greenwich Mean Civil Time)— continued.

30

Magnetic Declination (east of north) : 16 + tabular minutes. Day of Month. 'No.ofj Oh. lh. I 2h. 3h. I i Day. j , 4b. 5h. I 6h. 7h. i I 8h. 9h. lOh. I I I - I lib.. 12h. 13h. | 14h. • 15h. 16h. 17h. | ISh. 19h. j 20h. 21h. 22h. : 23h. Mean. I 1918. October 1 2 .. 273 .. 274 57-1 55-6 59-1 59-2 ) 62-2 ! 60-1 60-9 ( 61-0 60-2 58-2 55-7 56-5 59-9 58-2 564 52-6 53-1 I 43-1 52-0 I 56-9 53-7 52-6 55-9 I 49-9 j 53-7 54-3 j 54-2 54-3 j 54-0 ! 54-8 j 55-9 | 54-8 j 55-5 | 55-3 571 I 57-1 i 554 58-2 | 54-8 57-6 59-6 I 57-6 56-5 56-5 j 56-5 i 56-5 57-6 ! 57-3 56-6 57-0 j 57-0 57-1 I 55-7 57-6 57-4 57-1 57-3 57-6 1 56-4 55-9 1 54-3 56-5 53-1 53-3 53-1 55-9 51-4 55-4 57-1 59-9 59-3 58-8 ( 59-1 56-5, 54-3 54-2 51-0 52-6 53-7 56-3 3 4 5 6 7 .. i 275 .. (276 .. I 277 .. ! 278 .. 279 j 56-6 55-6 55-0 54-8 55-4 58-2 59-3 58-2 58-8 60-5 60-5 I 614 61-6 62-2 61-6 61-6 614 I 62-7 62-8 ! 644 59-8 54-5 ! 56-5 57-6 61-0 57-3 | 58-2 I 56-9 61-0 59-9 j 57-5 57-3 61-7 58-9 58-2 j 57-6 62-9 59-9 i 57-9 55-4 55-5 56-5 57-6 , 56-5 i 60-5 59-0 ( 58-8 I 58-2 I 54-3 j 53-2 j 49-4 , 49-8 52-6 | 56-1 I 554 ] 56-5 57-6 | 57-1 I 57-7 j 61-0 I 58-2 57-1 54-8 I 52-3 ! 49-8 ( 49-8 I 52-0 ( 56-4 I 554 ! 55-5 55-9 55-5 j 58-8 I 57-1 ( 56-5 56-5 54-3 ' 52-0 j 51-4 50-3 50-3 56-1 '■ 56-5 I 57-6 56-6 , 56-5 ( 56-5 56-5 ' 56-4 55-4 ! 53-1 ( 53-1 50-3 50-5 ( 52-4 56-3 55-9 \ 55-9 56-5 564 1 55-9 57-i 57-9 564 54-3 51-0 50-3 514 54-3 56-8 56-5 I 54-3 54-4 55-9 - 54-8 53-1 57-6 54-3 61-0 57-6 ' 54-8 i 57-6 58-8 57-8 47-6 ! 53-7 56-5 56-5 j 56-5 I 56-6 j 56-5 55-9 j 54-3 ; 52-0 ! 50-9 51-4 I 53-1 58-1 56-5 ( 55-9 56-4 | 56-0 | 55-9 55-9 ! 56-5 554 ( 54-3 ; 52-0 [ 49-8 51-4 ': 53-1 55-7 56-6 56-5 564 564 ( 564 56-3 j 56-3 56-1 54-6 52-6 51-7 I 51-3 i 52-8 56-8 56-5 j 564 57-4 j 56-4 ( 55-9 56-6 j 55-9 55-6 \ 54-7 I 52-7 I 50-5 ( 50-8 I 52-7 56-8 8 9 ,, io ,, 11 12 .. j 280 .. 281 .. 282 .. 283 .. 284 ! 57-7 65-0 55-9 55-9 55-5 60-5 64-4 58-8 59-3 59-2 63-3 i 63-3 67-2 : 68-7 61-0 I 57-6 62-2 62-2 61-8 : 63-1 62-2 59-9 i 594 I 59-1 67-8 65-0 61-7 > 58-2 53-1 58-8 57-6 I 54-8 614 59-6 58-2 I 58-2 62-2 60-9 ! 59-3 \ 58-3 ,, 13 „ 14 „ 15 ,, 16 „ 17 .. 285 .. 286 .. 287 .. j 288 .. i 289 55-8 56-6 57-8 59-1 58-2 59-2 58-8 60-2 61-8 58-8 62-2 62-5 61-6 ( 61-7 61-6 i 624 65-3 ; 67-7 59-9 I 59-3 61-6 59-4 57-9 j 57-6 60-8 59-2 58-2 j 57-6 61-6 61-0 59-8 59-3 67-8 62-7 62-7 j 57-6 60-5 j 60-1 59-9 : 52-6 57-2 57-1 56-9 57-6 [ 57-4 56-5 | 59-3 I 59-9 57-6 53-1 : 52-6 j 52-6 52-6 56-6 j 56-6 56-6 56-5 56-9 i 56-2 56-1 56-1 ! 55-8 55-4 54-4 j 52-0 : 50-5 : 511 i 54-3 56-6 [ 56-5 ( 56-6 56-5 57-6 58-5 56-5 [ 56-4 55-9 ; 55-1 ! 53-1 53-4 I 53-0 I 54-9 57-1 54-8 j 50-1 j 52-6 ( 54-8 53-1 52-6 j 48-9 51-4 50-9 50-9 ( 51-4 53-3 : 55-9 55-6 55-4 I 47-4 46-4 | 42-1 52-0 52-0 j 53-3 52-0 ( 52-1 i 52-0 ! 52-1 53-8 - 57-1 554 54-3 56-5 54-8 59-9 55-3 56-9 55-9 54-3 53-7 53-7 51-4 53-1 55-9 56-3 52-6 1 55-4 I 55-3 57-6 55-3 55-4 53-6 55-9 54-8 50-3 50-8 52-0 53-7 55-9 56-5 I 57-1 56-6 57-6 64-3 52-1 ( 55-5 54-3 j 53-7 52-0 50-3 < 50-8 55-9 56-5 53-1 54-8 ! 55-9 56-5 56-5 57-6 56-4 55-1 i 53-7 52-0 j 50-9 j 51-0 53-1 56-0 574 56-5 55-4 j 56-6 56-6 56-5 ] 56-5 55-5 : 53-7 ; 52-0 [ 50-3 j 50-8 51-4 56-7 57-6 54-8 : 55-5 56-5 55-8 57-0 56-4 56-5 I 53-1 ] 49-8 48-1 ! 49-3 52-6 56-5 ,, 18 „ 19 20 „ 21 22 .. i 290 .. I 291 .. ! 292 .. | 293 .. | 294 58-2 55-5 58-2 55-1 55-6 60-5 57-9 59-9 59-0 59-0 62-2 62-2 60-5 ( 62-1 62-2 '< 62-3 62-2 : 63-3 1 62-2 I 63-3 _. ... .... . 60-5 58-8 55-4 55-4 61-0 59-3 57-3 57-5 61-6 60-5 58-8 57-6 62-7 61-6 59-8 57-6 62-7 61-6 ! 59-9 58-8 55-9 i 55-9 54-3 57-1 | 55-3 56-4 56-5 ! 49-9 49-8 57-1 57-3 57-1 55-9 56-6 56-5 23 24 „ 25 26 27 .. (295 .. I 296 - • i 297 .. I 298 .. | 299 | 55-9 56-8 55-6 j 57-1 > 57-0 1 I 60-5 59-5 57-2 58-9 58-8 ( 63-3 63-6 : 62-2 63-3 | 59-3 60-5 : 58-9 ! 59-7 | 60-5 61-0 63-3 61-1 59-3 58-7 63-3 62-3 61-0 56-5 60-5 59-9 : 58-2 ] 57-6 58-8 58-5 ! 57-1 I 57-1 60-9 59-9 I 58-8 57-6 59-4 58-2 57-6 57-1 60-0 58-8 57-1 57-1 59-9 59-3 57-4 56-6 61-6 j 61-6 60-5 56-6 61-3 j 59-8 58-5 56-8 I i 58-2 55-4 ! 55-3 j 56-5 57-1 554 : 58-2 57-6 j 57-1 57-1 57-6 | 57-1 57-7 57-5 | 57-1 ■ 55-4 j 53-1 j 53-1 52-9 53-7 54-3 56-6 54-8 I 52-6 I 51-4 | 49-8 51-5 53-7 56-1 554 ( 52-0 I 58-3 , 54-2 55-5 55-6 : 55-9 55-4 j 53-6 , 52-6 : 53-5 52-3 ( 53-5 56-7 554 | 54-8 55-9 : 55-9 55-7 56-5 57-6 57-1 : 55-4 j 52-6 52-7 52-6 j 54-8 56-6 57-3 56-5 ( 56-5 i 57-6 55-9 55-5 ; 55-3 56-5 I 55-4 | 53-1 52-6 52-6 53-1 56-5 56-9 j 56-5 56-5 I 56-5 56-5 57-1 j 56-5 55-4 i 53-1 I 52-0 ( 50-9 | 51-4 , 54-8 56-7 564 j 52-6 j 56-5 57-6 57-6 53-1 55-9 54-8 53-1 I 51-4 | 514 i 51-9 ( 554 56-2 56-6 I 56-6 ! 57-1 ! 56-6 57-6 57-1 ! 56-5 554 54-2 51-0 ( 49-2 ! 50-0 i 54-2 56-6 55-4 554 55-4 56-5 56-5 57-5 56-4 54-4 j 52-0 50-2 ; 49-8 49-8 54-3 56-1 54-7 j 50-9 53-7 ; 57-6 56-6 55-8 54-4 53-7 ( 52-0 49-8 50-1 52-0 54-6 55-8 554 55-0 55-8 - 56-2 56-6 : 56-2 56-1 55-4 - 54-0 52-3 51-0 j 51-7 53-9 564 „ 28 „ 29 30 „ 31 .. i 300 : .. 301 .. 302 .. 303 I ! 56-8 58-5 57-1 : 57-i 59-8 60-0 59-9 58-1 61-0 60-6 61-6 j 62-2 61-1 i 61-6 61-0 i 62-3 ___ 57-5 57-1 56-5 57-1 I 57-1 | 56-6 I 56-5 56-6 56-5 54-3 ( 56-5 j 53-8 I ; r Means I i i i I I 56-8 61-8 ( 62-3 56-5 55-6 j 55-6 59-5

31

0.-1 A

Table of Hourly Values (Greenwich Mean Civil Time)— continued.

Magnetic Horizontal Force : 0-22000 C.G.S. + tabular y. Day of Month. of Oh. I lb. 2h. 3h. 4h. | 5h. 6h. 7h. 8h. 9h. 10b. llh. 12h. 13h. 14h. 15h. 16h. 17h. 18h. 19h. 20h. 21h. 22h. 23h. Mean. I III II ■ I I l 1 ! I i i l-l > 1918. ictober 1 2 J5 -H 3 4 5 6 7 8 9 „ 10 » 11 12 „ 13 „ 14 ,, 15 ,, 16 „ 17 „ 18 ,, 19 ,, 20 » 21 „ 22 .. I 273 272 - 275 282 280 292 309 309 309 321 j 331 324 . 294 309 333 302 304 307 307 309 306 277 289 j 280 271 300 .. I 274 256 I 280 : 285 300 314 i 305 303 326 311 317 325 I 300 309 308 310 312 312 298 312 310 299 294 ! 285 276 301 .. 275 266 288 298 310 I 311 , 295 I 289 300 308 j 330 310 : 308 315 315 310 I 312 305 308 303 ! 305 286 278 ( 271 254 299 .. 276 270 I 267 303 298 : 291 ! 296 ( 298 289 291 293 i 318 I 303 ' 304 i 306 | 307 300 307 312 309 I 302 280 312 I 268 261 295 .. 277 ( 265 I 279 288 302 317 320 I 313 308 306 j 313 ( 311 315 313 315 320 315 320 [ 320 320 318 320 281 ! 269 262 305 .. 278 ( 263 | 264 279 294 I 303 316 i 308 , 311 315 316 313 313 320 315 313 I 314 314 I 322 319 314 300 286 277 272 302 .. 279 I 279 285 294 307 271 310 j 316 ( 314 319 315 311 311 ] 311 ( 321 317 310 307 j 311 314 315 312 300 293 289 305 I I # .. 280 289 291 : 301 311 322 328 | 325 307 : 312 - 307 I 304 316 316 | 303 307 j 307 325 342 294 247 275 252 j 235 230 298 .. 1 281 241 263 256 268 ( 276 294 ! 275 298 ( 307 ' 294 j 298 295 289 ' 291 295 295 297 299 293 300 ( 287 278 > 276 271 285 .. I 282 266 265 281 293 I 290 304 ! 307 308 ! 306 313 ! 306 311 306 : 304 ] 304 304 304 305 307 307 I 306 294 i 284 274 298 .. j 283 266 273 286 295 I 305 316 i 315 314 316 317 - 317 314 305 ' 309 309 309 311 313 315 313 '■ 305 300 ! 293 285 305 .. | 284 280 277 282 299 j 312 326 320 319 314 321 ( 321 321 316 317 314 315 j 315 311 311 311 311 301 290 268 294 .. (285 266 i 287 293 299 ( 314 316 316 j 316 316 316 316 318 j 316 I 319 315 314 314 i 316 I 317 ! 316 j 316 308 291 j 280 308 .. j 286 282 : 287 296 303 ( 313 318 ( 317 I 321 322 ( 323 321 323 323 ( 316 318 322 319 I 324 325 324 ( 318 313 308 307 315 .. j 287 310 ! 316 ( 329 i 336 i 340 340 315 | 320 326 I 315 324 322 309 I 295 300 ' 306 306 308 309 304 ! 295 298 281 : 286 312 .. ! 288 286 ( 286 306 344 I 276 ,308 268 I 299 235 203 247 198 215 249 167 251 222 245 229 229 | 215 233 240 i 242 250 .. j 289 252 : 250 : 250 263 268 268 \ 258 | 247 253 257 264 277 271 267 j 275 i 291 283 268 272 273 233 240 232 247 261 .. 290 244 : 256 271 277 : 283 292 , 279 265 : 273 280 ( 273 288 301 278 ; 293 283 i 282 300 \ 287 299 ( 275 255 l 253 , 256 277 .. 291 256 266 j 271 | 288 282 292 | 290 2-77 , 282 299 I 286 290 290 . 295 306 300 i 314 285 285 292 j 284 275 ! 232 | 225 ! 282 .. 292 230 257 267 i 282 . 279 279 j 284 282 ' 279 282 261 279 ! 275 '' 278 284 289 284 286 284 | 275 ( 269 262 i 256 252 : 273 .. 293 242 244 j 252 ; 274 284 289 I 270 298 286 290 292 294 300 310 298 306 306 305 314 307 I 287 273 263 261 I 285 .. 294 255 255 | 275 283 280 289 : 305 299 298 297 298 305 307 294 ' 306 297 292 299 301 302 i 289 274 264 258 288 - „ 23 ,, 24 „ 25 26 „ 27 .. 295 262 274 279 294 308 301 306 309 313 327 300 302 302 294 302 299 296 299 318 310 306 285 ' 271 i 268 297 .. .296 267 266 272 I 289 295 303 305 317 326 299 294 : 298 304 312 ! 311 300 301 305 309 311 ( 292 288 ( 285 ! 277 297 .. : 297 274 j 281 296 311 316 316 318 315 317 i 317 308 i 313 310 291 ( 297 304 301 304 ; 307 305 i 303 293 ! 287 282 303 .. j 298 275 ( 290 300 305 310 311 312 313 310 j 310 315 ' 312 311 306 I 306 305 304 308 . 309 310 307 300 : 289 j 275 304 .. 299 286 291 299 309 306 307 300 302 304 ( 303 306 306 320 309 ( 308 309 309 312 313 - 310 | 301 296 ; 285 ' 278 303 - _..'-. __.i_.___ __.__._.. I ... i _.__ ___ _. - -_ ... . . . .. . ■ .. __.._.. ___ ___ ... „ 28 ,, 29 » 30 „ 31 Means .. ■ 300 | 293 306 318 ! 321 323 321 313 ( 314 317 319 319 325 304 298 313 322 313 295 309 306 ! 307 292 279 270 308 .. I 301 288 296 291 ( 313 313 313 j 308 308 307 ; 308 313 312 313 306 : 306 312 310 313 308 I 305 295 291 265 269 303 .. 302 274 256 251 277 311 310 310 - 313 314 ( 310 314 , 321 314 316 308 309 307 314 317 ( 315 305 301 291 ; 274 301 .. | 303 ( 276 294 304. 321 309 312 279 301 278 ( 259 ; 272 291 303 277 279 316 j 289 296 290 : 290 281 281 276 j 278 290 ... .. 266 276 286 298 300 307 301 304 303 303 303 302 303 302 300 ( 304 ( 302 304 303 : 301 291 285 ( 273 ( 268 , 295 ' I I . • I - - . . I I . . I ' ' I I I

C.—la:

Table of Hourly Values (Greenwich Mean Civil Time)— continued.

32

Magnetic Declination (east of north) : 16° + tabular minutes. Day of Month. K?- of Oh. | lh. 2h. I Day3h. 4h. I 5h. : 6b. 7b. Sh. 9h. ( lOh. llh. | 12h. i 13h. 14h. loh. 16h. 17h. 18h. I 19h. j 20h. 21h. ( 22h. 23h. Mean. I i III 1918. November 1 .. : 304 57-2 j 58-7 59-8 59-4 j 59-3 59-7 58-7 57-3 56-5 57-1 54-3 58-2 57-1 53-7 55-9 57-7 57-2 56-4 55-8 58-1 57-5 57-1 57-1 57-6 I 57-1 57-1 55-4 57-3 ! 57-6 57-6 ( 57-3 I 55-4 55-9 56-5 56-5 56-7 57-2 56-9 54-8 52-1 49-6 49-2 50-3 53-3 55-9 57-3 ■ 2 .. 305 57-7 61-5 I 63-8 62-7 : 62-2 I 61-4 58-9 3 .. 306 58-2 ■ 61-6 , 62-2 62-4 61-6 | 60-0 58-3 „ 4 .. 307 58-4 62-2 63-8 63-5 ■■ 62-3 | 60-6 58-4 5 .. 308 57-6 59-7 62-3 62-5 ( 61-0 59-3 58-2 6 .. 309 57-6 60-3 61-6 61-0 ; 60-5 ( 59-3 ( 58-2 7 .. 310 57-5 j 59-9 i 62-4 62-3 i 61-1 : 60-3 I 59-3 ,', 8 .. 311 574 60-3 1 564 61-5 61-0(604 59-0 ,, 9 .. 312 57-6 59-9 61-6 61-4 61-0 | 60-5 59-1 ,, 10 .. 313 57-6 60-1 i 60-8 61-1 60-8 ! 59-2 58-2 „ 11 .. 314 ( 58-2 61-0 ( 65-6 66-4 67-2 | 63-3 62-2 58-2 57-7 58-1 57-6 57-3 56-5 56-4 56-5 57-6 56-5 58-1 i 58-2 55-9 54-3 52-5 51-7 52-9 54-7 57-3 56-2 56-5 57-0 57-0 57-1 57-0 | 56-5 55-5 54-2 51-7 50-5 50-9 54-8 56-9 56-4 56-6 57-0 56-6 56-6 56-4 | 56-1 54-4 52-6 50-2 48-1 : 49-2 53-5 56-8 56-7 57-1 , 56-4 56-3 56-3 55-9 | 55-4 54-3 52-5 50-6 49-5 ( 50-7 54-8 56-4 56-6 56-6 j 56-5 56-4 56-2 56-5 ! 55-3 53-0 52-0 | 49-9 49-2 I 51-0 54-1 I 56-3 54-9 55-3 ; 56-5 56-5 56-3 56-4 : 55-8 54-4 52-6 I 51-0 50-6 51-4 I 54-3 I 56-7 57-0 56-5 ( 56-5 55-9 55-5 55-5 ''. 55-3 54-4 52-9 ( 51-6 50-7 51-3 j 53-8 56-4 56-6 56-3 55-4 56-3 56-5 57-2 j 56-6 55-2 52-9 j 51-9 49-8 52-0 j 53-9 56-8 54-8 54-8 53-4 54-7 55-8 54-3 51-9 54-4 53-4 52-0 52-6 53-0 55-4 56-2 54-9 54-8 54-1 55-4 53-9 53-0 55-4 53-0 53-1 | 52-6 52-2 51-6 54-7 56-6 51-8 49-6 49-6 | 52-1 55-4 56-4 54-9 58-0 54-7 52-9 52-8 511 52-8 i 55-3 56-4 55-9 55-3 54-9 55-1 55-8 | 58-2 59-2 58-2 I 52-9 49-0 50-1 ! 53-0 56-3 50-9 54-4 54-7 56-3 55-7 55-5 j 55-2 57-2 56-4 55-4 51-6 50-7 52-6 56-4 55-8 55-9 54-9 56-5 56-3 54-4 59-4 57-6 54-8 52-0 47-0 47-0 51-7 56-2 51-6 53-8 ( 52-2 52-0 55-7 57-6 56-5 ; 56-6 55-2 51-1 50-2 49-8 53-1 55-8 58-5 58-2 57-4 I 57-1 58-2 J 58-1 58-0 57-7 58-4 58-2 57-5 57-2 57-7 57-9 I 57-2 56-5 60-5 50-3 52-6 53-1 58-5 58-2 58-4 57-7 60-5 12 .. 315 55-9 58-8 60-0 61-1 62-2 j 63-1 58-9 13 .. 316 55-4 58-4 60-2 61-5 60-2 '. 60-9 i 60-3 14 .. 317 55-9 59-2 61-1 61-6 61-7 60-3 ' 59-0 15 .. 318 55-9 594 61-0 61-8 61-6 61-1 ! 59-8 16 .. 319 54-9 58-8 | 62-1 63-3 63-3 60-3 ! 60-0 58-2 56-4 58-2 58-8 57-6 58-2 53-8 49-8 52-6 56-4 54-3 58-8 57-6 58-2 57-7 54-8 57-1 58-8 55-4 55-9 55-9 57-6 55-4 54-5 j 53-7 17 .. 320 ( 55-4 ( 59-2 i 61-7 62-6 62-7 61-5 59-4 18 .. 321 ! 55-5 58-8 60-5 62-2 61-5 60-5 59-8 19 .. 322 ! 54-9 58-9 62-3 62-7 61-7 60-5 59-3 20 .. 323 55-6 59-7 I 62-7 63-3 62-6 62-2 60-9 21 .. 324 57-1 61-0 ( 63-3 63-8 63-6 63-6 62-0 22 .. 325 57-6 j 60-1 62-3 63-4 62-7 ( 61-5 60-6 23 .. I 326 56-6 | 60-0 j 62-7 64-2 65-6 | 66-4 61-1 24 .. : 327 60-0 60-9 60-1 59-3 57-7 I 56-5 57-5 25 .. 328 57-1 59-9 I 60-9 62-1 60-3 58-2 57-2 26 .. 329 ( 58-7 62-1 62-8 62-7 60-6 I 58-9 j 57-7 _____-L3 27 .. 330 58-1 ! 59-1 59-3 59-3 58-9 57-9 ' 57-7 28 .. 331 58-0 59-8 61-1 61-6 61-0 [ 59-9 58-4 29 .. 332 58-5 60-1 61-5 61-6 61-1 60-1 I 584 30 .. 333 59-3 62-6 64-1 63-2 61-6 59-7 j 57-6 Means .. .. 57-2 60-1 61-7 62-2 61-6 60-6 j 59-1 58-8 57-5 58-4 59-9 59-9 58-8 58-2 56-3 ! 53-4 57-5 57-1 57-1 I 57-5 58-4 58-2 57-6 57-5 59-9 58-5 57-9 57-1 59-9 58-8 57-7 58-1 59-9 574 57-4 57-0 57-7 59-9 58-8 58-3 j 56-1 57-1 53-8 52-8 50-3 57-4 57-2 55-6 ' 55-4 57-0 57-0 57-4 57-2 57-7 57-1 57-2 ( 56-9 I I 53-0 53-7 55-9 53-4 57-6 56-3 55-3 | 55-3 54-6 52-6 ( 511 51-9 54-2 56-4 56-1 55-8 55-6 58-8 56-5 ( 55-5 55-2 I 53-3 52-6 49-6 48-8 51-3 52-7 j 56-2 55-1 54-2 54-8 55-4 54-5 ( 55-3 55-4 53-4 53-1 48-6 50-9 52-0 | 53-1 56-2 55-2 55-9 56-3 i 56-4 56-4 56-5 55-8 54-3 52-0 49-8 49-1 50-5 j 53-3 ; 56-7 54-3 55-3 52-8 55-3 55-8 ! 55-7 55-3 | 54-8 53-7 50-8 50-3 50-9 ( 53-9 57-0 56-5 56-1 56-5 56-7 56-6 57-1 57-3 , 55-9 52-9 48-6 48-5 50-5 54-2 57-0 63-3 50-7 48-9 i 52-6 55-6 51-4 55-4 56-5 54-8 52-0 52-8 53-7 58-8 56-5 55-9 51-0 52-0 55-4 I 57-4 ( 57-1 ! 54-8 ( 54-2 54-6 52-6 52-2 52-1 54-3 ( 55-9 57-5 57-0 56-9 I 57-6 57-2 - 57-1 58-1 55-4 53-1 50-3 j 49-8 52-8 55-4 j 56-8 56-7 56-6 56-5 I 56-5 56-6 56-4 55-5 54-2 52-2 50-6 ( 50-2 514 55-3 ! 56-7 564 56-6 56-5 56-6 56-7 56-5 56-1 j 54-8 53-1 ( 511 50-2 52-1 55-4 ; 56-1 56-5 55-4 59-6 55-8 55-8 55-5 54-9 - 53-3 51-0 : 50-3 49-9 52-0 55-7 I 56-6 56-9 56-5 55-6 54-3 53-3 53-7 55-3 56-9 ! 57-6 ; 55-2 55-7 56-5 57-1 57-3 56-2 55-9 53-7 56-9 ( 56-1 57-0 57-6 60-5 j 56-3 53-0 51-9 53-1 54-9 57-4 55-7 55-2 55-1 | 55-8 , 56-1 ( 55-9 56-0 55-4 53-8 ' 51-4 50-5 51-5 54-3 56-5 ! I ! - . i 56-5 58-1 57-9 56-6 56-5 55-9 55-5 : 56-5 58-1 | 58-1 i 57-3 I 58-2 57-9 I 57-6 ( 57-6 57-1 56-6 I 56-4 56-6 57-2 58-0 56-8 56-3 | 56-1 I

33

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Table of Hourly Values (Greenwich Mean Civil Time)— continued.

5—C. Ia

Magnetic Hbiizonta! 'orce : 0-22000 + tabular y . Day of 3Ionth. (No. of Day. Oh. lh. 2h. 3h. | 4h. "5h. I ! 6h. 7h. 8h. 9b. 10b. llh. i 12h. 13b. | 14h. 15h. 16h. | 17h. ' 18b. 19h. 20h. 21h. 22h. 23h. (Mean. i-i I I 1918. November 1 304 282 285 294 I 299 | 312 310 303 308 309 309 I 331 310 ! 304 _._._. - ,.„H _.__. -j. _. .„ 302 302 ( 304 307 308 313 307 291 275 274 264 302 289 282 277 303 290 281 277 313 288 274 271 307 299 290 289 302 2-95 287 ( 282 300 2 3 4 • 6 7 8 9 10 11 305 306 307 308 309 310 311 312 313 314 270 283 277 281 288 288 281 271 281 291 280 296 287 302 293 301 285 293 295 313 292 315 299 315 311 317 294 308 307 298 292 316 312 320 315 314 308 315 317 320 323 325 313 320 326 327 331 331 305 315 321 323 323 325 317 I 320 320 293 | 330 327 291 290 305 300 293 304 290 299 322 291 328 328 274 313 296 313 305 319 317 322 328 319 323 322 296 319 302 303 300 305 308 308 308 312 316 319 321 313 313 316 322 321 323 326 319 I 326 330 325 325 324 324 324 324 324 328 328 32-9 323- 331 333 323 296 278 313 276 : 304 | 309 •310 311 323 319 321 318 318 313 314 310 | 321 322 330 316 313 314 j 298 298 306 ( 317 309 309 309 310 ( 310 313 315 316 318 I 319 320 ( 321 324 317 I 316 314 315 314 315 I 315 313 317 317 1 310 317 317 ( 319 319 I 321 316 324 ( 316 '■ 318 319 316 318 I 314 322 313 312 I 324 j 318 j 317 313 305 i 301 ! 300 297 312 310 317 315 325 i 326 313 313 320 317 320 319 324 321 320 , 316 319 ( 315 315 ( 292 311 305 [ 291 285 312 304 ( 294 287 310 ; 293 I 281 275 305 305 : 289 297 271 : 275 261 I 241 301 306 310 311 311 315 312 313 313 295 12 13 14 15 16 315 316 317 318 319 256 258 254 274 247 255 267 274 269 257 243 277 268 292 279 302 304 307 311 299 295 292 I 312 290 297 312 287 290 298 299 ( 299 289 296 306 ( 301 296 305 290 ( 290 285 275 309 295 i 290 300 I 288 299 i 302 292 | 294 . ! 307 288 279 ( 285 282 236 298 289 -290 298 301 300 294 ; 2-94 299 304 321 321 ! 306 296 302 297 288 : 294 287 265 - 280 292 j 293 293 : 276 319 : 301 278 ( 292 265 265 253 253 268 269 238 j 253 273 271. 258 | 269 289 257 j 235 247 281 . 255 248 j 260 281 283 288 295 283 i 17 18 19 20 21 320 321 322 323 324 "273 259 269 267 281 274 271 259 273 -294 280 281 286 280 296 292 295 316 300 297 315 299 313 320 297 312 323 308 323 341 320 315 313 320 308 306 310 308 311 307 298 297 296 316 307 305 315 320 322 320 309 321 318 311 321 I 300 : 2-91 294 I 297 | 316 ( 309 320 i 318 I 311 - : 303 _.„, : __„ > ,.. i „„_ i ■ I 303 300 I 299 295 ! 298 i 310 309 308 301 305 312' 306 : 323 306 310 317 317 i 315 319 327 303 304 ( 303 . 303 307 291 291 i 301 ; 305 315 312 328 322 311 308 289 279 271 262 292 283 278 270 303 291 283 275 308 294 280 274 291 279 269 259 294 295 303 308 303 •'■■' I 22 23 24 25 26 325 326 327 328 329 265 281 269 231 267 278 285 284 245 284 300 295 294 268. 287 311 317 323 294 226 302 300 291 298 282 j 292 297 299 j 306 I 308 315 283 286 284 304 327 327 329 318 293 276 257 252 294 299 : 301 292 291 290 296 296 297 301 301 311 304 301 302 306 312 312 311 319 314 311 318 316 288 286 290 294 308 307 304 306 313 : 315 254 I 244 290 ( 223 297 ! 298 302 ( 305 308 308 312 307 329 329 297 302' 306 ! 302 311 ! 310 I 310 314 317 253 ' 281 I 277 259 262 229 ■ 306 282 282 287 , ] 297 j 297 297 299 i 295 ( 306 : 303 303 304 : 307 305 303 306 305 307 322 311 318 302 308 332 340 354 342 342 299 299 299 303 ! 292 303 308 307 305 306 320 j 315 255 ' 252 286 260 301 294 307 302 300 277 263 : 268 238 227 231 246 264 256 246 233 279 258 257 257 290 277 267 254 306 263 277 283 295 27 28 29 30 330 331 332 333 277 282 276 266 298 296 294 I 255 308 308 297 264 31.1 321 | 316 315 318 ; 315 305 305 320 304 299 302 303 313 315 289 305 300 310 303 339 322 295 287 270 278' 271 271 299 279 266 256 309 305 276 281 282 272 271 271 291 280 269 267 300 304 315 288 I i ! ! i Means 272 281 292 303 309 316 303 316 309 307 307 302 307 298

C—la.

Table of Hourly Values (Greenwich Mean Civil Time)— continued.

34

Magnetic Declination (east of north) : 16 —(— tabular minutes. Day of Month. of | Ob. lh. 2h. Day. | 3b. I 4b. 5h. ( 6h. 7h. ( 8h. I 9h. j lOh. llh. 12b. 13h. 14h. 15h. 16h. 17h. 18b. 19h. 20h. 21h. 22h. 23h. Mean. I I I I ■ t 1 I I I I I I I 1918. lecember 1 2 3 4 6 7 9 10 11 334 335 336 337 338 339 340 341 342 343 344 57-7 60-5 62-3 ( 63-3 634 62-2 614 [ 59-6 58-9(54-2 56-6(55-5 52-0 49-9 50-8 58-8 59-9 60-2 61-0 60-5 594 1 57-9 57-1 57-1 i 55-9 : 56-5 56-4 56-3 56-2 56-2 55-8 59-2 61-4 62-2 62-7 62-2 | 60-5 58-8 58-1 56-5 ! 51-4 51-2 48-5 50-5 54-1 55-9 60-2 62-1 62-1 j 61-6 i 60-5 j 59-3 57-3 57-5 56-5 ! 53-5 55-3 54-5 I 55-8 55-7 54-9 56-9 58-2 59-7 I 59-8 ! 59-9 59-2 j 58-1 57-9 : 57-1 57-2 56-5 j 56-6 | 55-9 56-5 57-0 59-9 61-7 62-1 ( 61-0 ' 60-6 59-2 j 58-5 58-2 j 57-6 57-1 57-0 | 56-6 ( 56-5 564 57-6 60-2 60-9 \ 61-5 j 61-0 I 60-9 j 59-3 58-5 58-7 | 55-1 56-7 56-6 : 56-5 ( 51-4 52-3 54-7 58-8 62-5 66-5 I 65-4 , 67-3 67-9 65-0 61-6 } 57-0 52-7 49-8 : 44-1 , 34-8 46-5 56-4 60-3 61-6 63-3 I 65-3 ! 60-5 63-4 ! 62-7 58-2 ( 57-9 52-0 52-6 51-4 ; 50-5 48-5 53-7 57-0 59-3 61-0 j 62-6 j 61-1 59-9 56-5 58-8 I 55-8 j 54-8 53-7 54-3 I 50-9 54-7 54-2 57-3 59-9 61-6 ; 62-7 I 61-5 60-7 59-3 58-2 - 57-7 j 57-5 55-8 54-8 i 55-4 55-3 55-3 56-9 58-5 59-3 ■ 59-7 ( 60-6 60-1 59-0 58-1 57-9 I 57-9 56-9 ( 56-9 ! 55-9 55-3 57-1 | 58-2 59-3 57-3 j 59-6 | 60-9 59-3 - 59-9 58-4 ! 58-8 I 57-2 56-9 ( 56-6 : 58-2 55-3 56-6 i 57-5 58-4 59-8 j 60-0 | 60-0 : 59-3 j 58-0 57-1 56-3 55-9 55-3 56-9 ! 58-2 55-3 58-7 I 60-6 61-6 60-1 i 60-5 I 60-1 , 59-8 I 59-1 55-5 | 56-6 < 57-1 57-3 j 55-7 ( 55-9 54-3 58-0 I 61-7 i 62-7 : 62-5 61-6 : 60-5 59-3 - 58-7 55-9 57-1 57-4 57-1 ! 57-0 j 55-1 55-9 ii : 50-3 50-3 53-0 56-3 56-1 55-8 54-6 58-7 56-9 57-1 57-6 55-8 56-3 55-9 55-7 56-1 55-8 54-8 53-1 53-9 53-3 43-6 52-0 52-8 55-3 54-7 55-5 54-2 58-7 57-0 57-7 I 56-7 j 56-7 54-8 | 56-5 54-4 57-9 57-6 56-6 56-6 54-3 52-8 50-8 49-9 50-3 52-6 56-2 55-8 52-2 52-0 52-8 51-2 52-8 55-8 554 53-7 51-4 50-9 51-6 53-1 56-4 54-9 53-0 : 50-8 50-1 50-9 ; 53-1 56-0 54-2 53-3 i 50-9 50-1 51-4 ' 54-5 56-7 53-0 52-1 : 52-6 50-8 52-0 53-1 i 55-9 58-2 53-1 52-0 50-9 j 52-8 55-1 j 55-2 55-3 55-3 54-4 55-7 I 53-7 | 53-3 56-6 56-4 52-5 50-9 50-3 514 52-0 j 55-7 55-5 54-4 56-2 52-0 51-2 ; 52-9 j 56-9 53-0 52-0 : 50-9 51-3 51-0 53-7 ! 56-0 58-4 53-7 52-5 52-7 54-3 ( 55-2 : 57-0 54-5 52-8 52-3 53-1 54-1 I 55-9 56-3 53-7 52-7 ' 52-1 51-6 52-3 j 54-8 '• 56-4 53-1 50-8 49-8 49-3 50-3 \ 52-2 56-2 12 13 14 15 16 345 346 347 348 349 54-8 | 55-4 ( 54-7 55-1 55-7 57-9 54-5 I 54-4 55-4 54-3 54-6 53-7 54-3 54-4 53-5 17 18 19 20 21 350 351 352 353 354 ( 56-6 : 61-8 : 65-5 65-5 64-0 60-9 ( 59-1 : 57-6 57-1 57-5 51-7 54-7 55-9 55-8 564 | 58-4 63-4 j 66-2 i 65-7 63-1 61-2 j 59-3 ''• 57-1 I 55-3 55-4 55-5 56-3 : 56-2 56-5 56-5 57-1 62-5 : 65-6 66-6 66-1 I 62-7 59-9 57-1 ! 57-1 54-3 ! 52-6 42-1 48-5 53-9 55-9 584 58-8 I 60-3 62-5 ( 61-0 ( 59-7 ; 58-5 57-9 57-6 57-1 ( 57-1 55-9 54-3 57-1 55-8 57-9 59-3 I 60-6 614 1 61-6 l 59-2 57-1 57-0 55-9 53-7 ! 52-6 544 54-6 55-9 55-7 544 1 57-2 58-4 59-3 ; 61-0: 61-2 59-9 : 58-7 57-2 57-1 57-1 57-2 57-1 56-9 56-5 ' 56-5 I 58-8 61-1 62-2 ; 60-8 60-6 : 59-0 j 58-8 57-1 i 58-1 58-2 55-9 54-5 55-7 55-9 564 ( 57-5 58-2 58-3 57-1 58-0 57-9 58-2 57-3 57-1 56-7 57-1 55-6 57-3 52-6 54-8 56-3 57-7 58-2 59-1 59-8 61-6 62-5 60-5 59-1 ( 55-8 56-5 j 54-5 53-3 51-2 54-6 56-7 57-7 59-3 , 58-2 I 57-1 i 55-9 54-8 55-8 i 54-3 > 52-2 53-7 | 564 61-7 55-3 56-5 57-5 57-3 56-5 55-9 : 54-7 55-4 55-7 51-7 56-4 56-6 56-6 56-6 55-9 ( 54-5 _*- ■ | 544 51-2 49-2 47-9 50-5 54-3 56-6 54-3 50-7 47-2 45-2 48-6 51-4 56-3 55-5 52-9 50-9 49-8 51-3 52-8 55-8 53-9 54-8 53-6 50-3 50-2 55-9 56-7 54-1 53-7 51-1 ! 514 51-3 52-9 55-8 22 23 24 25 26 355 356 357 358 359 56-7 55-9 55-2 55-7 j 56-2 - 58-2 54-4 54-8 54-8 644 ( 51-3 48-1 54-8 I 54-6 . 53-5 53-7 52-0 : 49-6 50-3 51-2 544 56-2 56-4 55-7 53-5 I 53-1 52-6 54-7 57 -.1 56-5 54-1 52-6 : 51-6 51-9 534 : 55-8 55-4 60-9 55-8 49-1 52-3 54-8 ! 56-4 53-8 53-0 51-8 : 52-6 54-8 55-9 55-4 27 28 29 30 „ 31 360 i 361 ; 362 363 364 57-1 ; 59-1 61-2 61-2 60-5 ( 59-0'! 58-2 ■ 58-0 58-2 584 : 57-3 ; 57-3 57-3 , 57-3 57-1 ; 56-7 59-6 60-5 60-7 59-8 | 58-7 j 58-4 ; 57-6 57-3 57-6 57-5 57-7 j 55-9 55-4 57-1 58-8 62-2 62-8 62-9 ! 62-4 | 60-7 ! 59-9 ! 58-7 58-4 58-2 58-2 57-7 56-6 | 54-8 57-1 55-9 59-3 61-4 61-6 61-8: 60-7 59-3 : 59-3 584 58-1 57-9 57-3 ' 56-9 56-6 56-4 55-1 57-4 60-1 61-4 60-5 60-5 59-6 j 59-6 58-8 57-6 57-6 57-3 i 55-9 53-3 53-7 56-5 59-2 60-9 61-6 ( 61-4 60-6 59-7 58-4 57-7 56-8 55-8 55-3 j 54-8 54-6 54-7 57-1 57-1 ; 56-6 I 57-1 56-6 56-6 I 56-6 55-7 55-6 55-9 55-9 \ 55-5 55-4 I 56-2 55-1 56-1 53-9 52-6 ! 51-2 514 53-9 57-0 56-5 54-8 52-6 50-9 52-0 i 55-3 56-8 55-3 53-8 52-7 ( 51-4 j 51-4 I 53-4 57-3 55-2 54-1 52-2 50-8 ; 50-2 54-6 56-9 57-7 54-3 52-0 51-0 52-0: 53-1 56-5 55-1 53-6 52-0 51-2 ! 51-9 53-9 56-3 Means ■ .. I ! J i 55-4 55-5 | 55-0 I .. 54-7 55-1 53-6

35

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Table of Hourly Values (Greenwich Mean Civil Time)— continued.

6—C. Ia

Magnetic Horizontal Force : 0-22000 C.G.S. -4- tabular y. Day of Month. a ° f Ob. ! lh. 2h. 3h. 4h. 5h. !' ! 1 I ; .6h. 7h. 8b. 9h. j lOh. I lib. 12h. 13h. | 14h. 15h. 16h. 17h. 18h. I | | 19b. ! 20h. 21h. 22h. I 23h. Mean. 1918. December 1 .. 334 I 264 263 j 2 .. 335 ( 241 268 j 3 .. 336 I 267 280 4 .. 337 269 272 ,. , 5 .. 338 261 268 .6 .. 339 292 303 . 271 ! 283 275 ( 280 297 297 289 | 301 282 I 295 308 : 317 I I i 299 309 I 309 , 301 302 | 314 297 282 290 287 295 295 ! 291 j 301 315 321 308 327 320 ; 276 I 266 315 303 296 299 303 I 299 ! 298 307 312 | 307 I 301 ; 304 I 302 305 323 ! 322 i 319 : 317 ( 316 316 316 301 ( 314 294 I 302 : 304 300 ! 2-68 257 265 I 293 | 298 296 306 j 310 308 318 317 316 I . 1 | 302 | 308 335 292 281 256 254 200 j 215 243 284 299 294 297 ! 298 297 295 281 274 j 260 259 286 277 284 303 ( 313 295 287 280 260 242 258 I 286 297 ( 296 304 j 305 297 299 293 ( 276 : 261 261 - 293 309 ( 308 311 : 312 ; 313 311 304 j 300 j 291 - 291 i 301 316 315 316 317 315 308 304 ( 296 I 287 : 282 : 311 318 308 312 316 306 272 270 ! 255 244 , 240 306 319 268 256 ; 250 247 251 231 219 205 ; 225 I 264 313 289 288 : 297 j 275 267 262 ; 246 269 - 248 286 295 290 287 ( .286 j 291 279 246 ( 264 259 ': 254 283 298 298 ( 300 ( 303 302 289 283 : 292 280 , 283 297 7 .. 340 283 I 291 8 .. 341 250 | 256 9 .. 342 228 | 253 10 .. 343 241 248 11 .. 344 253 I 260 298 315 j 235 261 275 296 | 260 272 | 272 i 300 325 | 331 335 336 I 332 325 332 288 j 299 ■ 309 334 ( 287 273 257 311 | 364 ! 318 303 I 300 316 297 290 i 312 ( 309 309 ( 397 299 310 332 i 320 ( 311 312 , 316 ■ 306 304 322 327 334 j 261 : 301 258 277 287 296 299 307 285 300 318 304 . 12 .. j 345 ( 284 276 13 .. 346 269 291 14 .. 347 282 288 15 •.. | 348 285 295 16 . . 349 276 290 277 293 295 302 292 305 312 I 317 301 j 307 I 305 ' 315 304 j 313 319 : 311 312 322 ! 310 306 'I 314 313 I 314 313 299 ( 304 309 317 306 : 298 296 305 310 307 307 319 305 303 320 323 319 318 325 307 308 I 309 301 303 307 302 314 292 294 303 303 I 303 301 309 | 312 318 | 298 ( 295 300 i 308 326 324 329 i 295 276 [ 345 310 303 298 292 300 j . 326 307 307 303 298 298 : 287 286 274 ' 264 299 309 300 : 295 302 308 296 ! 286 264 286 274 300 315 303 ( 293 296 295 291 { 294 274 272 272 295 311 301 ( 301 304 304 298 ! 289 283 277 268 300 315 303 304 304 312 309 I 310 307 285 279 307 298 I 295 ] 299 307 304 303 ( 300 I 283 266 264 298 319 314 316 | 312 318 '' 318 j 313 293 274 ( 267 306 314 294 288 293 291 ! 295 I 287 273 286 i 279 298 315 293 315 325 301 ( 291 I 280 275 264 i 222 296 305 307 310 315 314 298 ( 208 299 278 j 261 296 303 308 305 310 312 313 314 296 290 I 285 301 298 302 302 303 308 300 290 275 259 : 251 296 317 306 307 310 309 312 312 304 293 i 279 307 430 308 264 291 264 193 173 141 1 180 i 185 282 284 293 282 285 272 279 261 208 ! 220 ( 237. 255 17 .. 350 270 ! 273 18 .. | 351 267 269 19 .. 352 271 j 282 20 .. 353 266 ( 269 21 .. 354 238 ( 258 286 ( 317 I 282 304 ! 292 315 i 284 276 272 292 303 323 J 318 312 i 313 300 315 ( 315 329 i 316 308 316 316 308 333 328 I 315 307 309 302 291 308 313 310 311 318 325 308 311 330 301 303 299 306 306 I 291 | 286 284 ( 285 '■ 296 I 312 : 293 - 297 ( 220 225 __.!__.! ___ _._ . __■■._. i 309 307 305 I 297 302 296 ; 313 321 312 327 334 318 277 270 290 22 .. j 355 269 - 272 | 23 .. 356 282 ' 277 I 24 .. 357 257 273 • 25 .. 358 281 290 j 26 .. 359 185 193 301 300 320 314 306 303 308 297 322 326 308 303 302 325 319 329 823 315 317 312 315 335 327 330 332 323 327 335 232 259 j 280 264 267 267 267 I 27 .. 360 236 241 28 .. ! 361 256 269 29 .. 362 260 277 30 .. 363 265 267 31 .. 364 292 j 302 243 268 j 282 294 ; 278 285 276 294 307 316 I i 279 290 284 280 275 I 274 | 272 298 296 293 282 283 ( 284 286 285 291 295 295, 294 294 291 307 309 307 300 295 297 302 318 320 316 322 320 321 322 271 271 271 289 284 285 291 289 289 301 297 301 325 325 302 269 269 269 j 271 275 279 275 270 255 250 268 280 283 284 : 284 284 279 272 263 257 254 280 283 286 285 j 284 285 283 274 266 259 261 283 299 300 300 | 302 303 298 ( 288 288 281 287 294 299 290 293 288 301 293 i 283 283 281 273 304 i I I I : I I i ! I : ! : - I I I I : I : 1 Means -.. .. 263 271 281 294 281 306 313 309 308 308 303 302 306 313 308 302 301 302 299 301 299 307 297 298 i 299 296 I 288 281 268 263 I 260 292 307 298 288 268 292 I I I - I I I

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MEAN DIURNAL HORIZONTAL DISTURBING FORCES, 1918, AT CHRISTCHURCH.

36

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37

Approximate Cost of Taper. — Preparation, not given; printing (1,100 copies, Including diagrams, Ac), £72 10j.

By Authority : Marcus F. Marks, Government Printer, Wellington.—l9l9.

Price Is. 3d.]

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Mean Monthly Curves of Magnetic Declination.

1918

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Curve showing Mean Diurnal Range of Declination at Christchurch.

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1918

Mean Monthly Curves of Magnetic Horizontal Force.

Curve showing Mean Diurnal Range of Declination at Christchurch.

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