C—lα,

8

A principal feature of the year's work has been the amount of time and work given to the demands of other Departments, such as in connection with Representation Commissioners and electoral boundary maps. The subdivision of land, as evidenced by the number of town plans sent in for the approval of the Minister, has not fallen off in number, but has increased in importance. The influence of more modern ideas as to public requirements in view of the growth of existing town and village nuclei, which is becoming more and more apparent, forces attention to consideration of aspects which did not receive so much attention in the past, such as the provision of sites for recreation and public buildings, &c. Amendments to existing legislation with the aim of rendering it more flexible so as to meet varying conditions have been prepared, and it is hoped that the whole subject may receive the consideration it should have in view of its importance to the well-being of the population. Draughtsmen's Examination. This examination had to be postponed owing to the pressure of other work of a similar kind ; and in order to avoid holding two examinations in one year, that for 1921 has been omitted altogether, the next being held about the beginning of August to get back into the slacker period of the year. Other Work. The cost of descriptions, maps, and other kinds of work done for other Departments amounted to £428 during the year; lithographs issued without charge, to about £15; and lithographs sold, about £410, of which about £250 represents other Departments' map requirements. These are from Head Office only, and do not include similar transactions in each district office. (b.) REPORT BY E. J. WILLIAMS, TIDE-COMPUTER. Computation op Harmonic Tidal Constants. The computations required to evaluate the harmonic constants used in predicting the tides of the six standard ports for the year 1923 have been completed. From, the harmonic analysis of the measured hourly heights of the tide-gauge records of any port extending over a period of 370 days is obtained one value of H (semi-range) and one value of X (epoch) for each component for each year of hourly heights analysed. For the larger tides M 2, S2, &c, the values obtained are fairly concordant. In the smaller tides, however, on account of tidal observations not being exactly in agreement from year to year, there are considerable discrepancies. Therefore it is necessary to extend the observations over a number of years, and to accept the mean of the values of H and X for each tide for the completed years of analysis as the best result. In accordance with the above the following table was prepared and forwarded to the Director, National Physical. Laboratory, Teddington, London, England, on the 21st May, 1921, for employment in the tide-predicting machine, and the tide-tables for 1923 were received in Wellington on the 24th November, 1921.

Table D. Mean Values of the Harmonic Constants used in preparing the Tide-tables for 1923.

Tide Symbol. _ Auckland. A,= 5-74ft. H. K. Bluff. A.-6-38ft. Dm A„ = ledln. i-23ft. Lyti A„ = telton. 3-20 ft. Wellington. A. = 2-93 ft. Wesl ;port. i-OOft. H. K. II. K. ll. K. H, K. II. K. ihort Period. SI S2 S4 Ft. 0-010 0-595 0-020 17-35 265-12 33401 Ft. 0-007 0-510 0-009 O 90-00 48-97 228-48 Ft. 0-015 0-243 0-006 O 10-22 129-73 309-00 Pt. 0-035 0-179 0-009 31-91 143-04 202-78 Pt. 0-004 0-098 0-004 O 244-84 332-36 196-76 Ft. 0-009 0-979 0-007 O 75-22 331-67 45-87 S6 Ml M2 0-003 0-011 3-805 55-73 144-69 204-90 0-006 0-017 2-857 170-45 88-42 35-47 0-003 0-012 2-497 117-97 89-75 122-56 0-015 0-010 2-879 344-95 99-40 125-63 0-005 0-007 1-597 300-88 38-55 130-60 0-005 0-013 3-759 329-46 340-03 304-11 M3 M4 M0 0-038 0-108 0-024 199-10 128-64 309-52 0-009 0-094 0-086 204-88 227-29 78-34 0-018 0-260 0-076 237-70 177-17 359-45 0-016 0-016 0-022 112-80 80-19 68-96 0-025 0-038 0-014 178-16 278-31 97-75 0-021 0-004 0-026 202-37 35-83 36-52 01 Kl K2 0-055 0-235 0-142 140-10 168-27 252-93 0-111 0-060 0-127 75-45 114-27 51-19 0-090 0-073 0-095 73-23 90-29 120-23 0-088 0-148 0-054 61-46 82-58 102-88 0-103 0-085 0-049 35-56 81-38 349-74 0-094 0-077 0-208 47-94 183-96 327-41 PI JI Q] 0-075 0-015 0-012 165-26 203-86 65-42 0-023 0-007 0-025 105-33 189-16 40-22 0-025 0-004 0-021 97-64 101-59 355-00 0-051 0-007 0-021 112-04 146-39 43-38 0-031 0-007 0-032 72-64 144-85 22-22 0-027 0-015 0-035 125-62 243-99 29-77 L2 N2 ?-2 0-171 0-793 0-190 202-92 172-38 197-96 0-113 0-657 0-137 34-42 10-61 57-71 0-162 0-538 0-008 108-52 103-73 123-60 0-088 0-663 0-148 148-45 95-31 122-05 0-054 0-397 0113 126-89 101-09 117-77 0-090 0-754 0-181 269-58 287-48 317-48 T2 (MS) 4 0-103 0-067 0-180 172-63 293-47 195-00 0-067 0-023 0-080 7-87 111-74 0-29 0-029 0-020 0-107 43-84 255-21 140-40 0-091 0-030 0-102 59-29 219-85 128-98 0-081 0-037 0-035 89-10 280-44 135-18 0-124 0-042 0-103 277-95 44-18 300-16 (2SM) 2 R2 0-004 0-023 303-96 214-72 0-046 0-015 121-57 151-90 0-046 0-016 0-78 171-69 0-006 0-013 25-99 150-12 0-031 0-017 351-88 119-81 0-072 0-039 204-28 259-57 Long Period. Mm Mf MSf 0-083 0-044 0-054 184-66 252-09 181-63 0-051 0-065 0-071 242-07 215-88 239-59 0-000 0-077 0-051 148-40 171-60 89-81 0-048 0-063 0-129 137-29 183-39 156-38 0-087 0-052 0-073 308-38 169-17 60-48 0-030 0-040 0-005 98-79 330-87 132-03 Sa Saa 0-223 0-065 46-05 113-05 0-085 0-125 54-84 04-34 0-126 0-081 257-97 88-94 0-097 0-085 246-56 139-91 0-073 0-103 277-94 145-40 0-093 0-131 96-39 161-95