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2

Table B. Observations for Azimuth, 1884-85.

Note. —The azimuth of the referring lamp has been found in all oases by means of " time azimuths" of <jOotantis. On the 14th March, 1885, the Survey Observatory, Mount Cook, Wellington, was dismantled, the instruments packed-up and left at the head office. C. W. Adams, Geodesical Surveyor.

APPENDIX No. 2. EXTEACTS FBOM THE EEPOETS OF CHIEF SUEVEYOES IN CHAEGE OF SETTLEMENT OPERATIONS IN DISTRICTS.

AUCKLAND. Mean Degree of Precision attained in Survey for the Period. —ln initiating the practice of calling on the surveyprs for the results of their trigonometrical and chain closures—which has now obtained for the last four years—the end sought was the collection of data from which an average mean of angular and linear measures could be obtained for comparison with similar operations elsewhere. It is a reasonable assumption, deducible from the tables given below, that in all classes of country, with ordinary care, the use of Troughton's 5-inch theodolites and Chesterman's steel bands will produce work whose average error will be 1J links per mile for minor triangulation of about two-and-a-half-mile sides, and 2 links per mile for measurements conducted over the surface. These results will bear favourable comparison with those obtained in other countries, deduced from the same class of surveys, and are highly creditable to the surveyors who produce them. Although the tables are confined to the work of the staff surveyors, that of several of the authorized surveyors, which comes before the department for check, is equally good. The Inspector at Gisborne supplies the results of twenty-two closures by authorized surveyors as 1-1 links per mile, as checked by himself in the field which shows the reliable character of their work. Major Triangulation. —ln the last annual report mention was made of the fact that the longdelayed triangulation of the King country had been started, and that it was then being carried on by District-Surveyor Cussen and assistants, and that good progress had been made, notwithstanding the difficulties inherent in working in a country so far from supplies. Mr. Cussen is now able to return an area of 2,719,000 acres of major work, the maps of which are deposited in the office; and within which area the topographical features have been depicted with a considerable degree of accuracy. Some opposition to the erection of stations was offered by the Maoris in isolated places ; but with the help of Eewi, Wahanui, and Taonui, and the tact displayed by Mr. Cussen, this has always been overcome. This opposition is due more to the desire on the part of local chiefs to assert their rights of ownership, rather than to any objection to the survey itself. The Maoris have now become so accustomed to seeing the survey parties traversing their district that little or no opposition is expected in bringing the work to a conclusion in the southern part of the district. The average length of the major sides in this year's work is 14'5 miles, while the mean defect from 180° in summation of the angles is 5"-8. The greatest difference in closure on the radial sides of the polygons (by which system the work has been computed) is o'6 links per mile, the least o'o7 links, and the average closure in ten polygons is 0-32 links per mile ; whilst the greatest correction applied to the external angles in any one polygon is 4""7, a quantity far within the limit allowed by the power of the instrument used. The crucial test of this work so far (until the Chief Surveyor, New Plymouth, can furnish the length of the Taranaki sides on to which Mr. Cussen has closed) is the closure on to the Taupo triangulation, which shows in a circuit of 270 miles a difference of 0-63 links per mile on the side, and a difference in bearing of 51", whilst the heights close on the same work to Bft. A further test of the heights is obtained from a comparison with those of the Public Works Department, as carried independently by them from sea-level at Auckland to Te Kuiti and Otorohanga, on the central line of railway, where the differences are Bft. and 13ft. respectively. In addition to the work shown as complete in the tables attached, Mr. Cussen has the stations up and angles partly observed over 1,340,000 acres, which will come into next year's results, when the whole of the country in this province to the 39th parallel will have been completed. I append Mr. Cussen's report on the character of the country, which, together with the map being prepared for publication, will afford detailed information as to its resources.

Locality. Station. Alt. No. of Obs. Azimuth of Referring Lamp. r o Distance to Referring Lamp. Referring Lamp. Alt. of Refer. Lamp. Feet. 258 o f // II II Links. •75 21143-5 Feet. 602 .uckland ... American Transit of Venus Station, 1882 20a Domain 108 60 Botanical Hill British Transit of Venus Station, 1874 and 1882 60 19 173 18 51-4 4-1 3-2 One-tree Hill 1610 V 1 107 Trig, pipe 42U.C. langonui ... 'auranga ... risborne ... lapier felson iurnham ... 186-4 68-2 428 330-7 470-7 219-3 12 22 21 29 30 30 184 47 36-8 8 21 01-9 8 02 23-2 180 33 04-6 193 22 25-3 350 32 55-0 3-5 5-4 3-9 5-1 4-6 5-1 3-1 4-6 3-2 3-9 3-8 4-6 •90 11086-8 71 26640-9 •71' 24099-2 ■71 16622-4 •70 33447-3 •84 10809-6 44997 947 15-i 2538-: 272-: | f apier 330-7 179 55 33-6 •9 13188-5 J 16m