C.—lA

4

Table C. Mean Values of the Harmonic Constants for Use in preparing the Tide-tables.

The tide-tables for the year 1926 of the six New Zealand ports (Auckland, Wellington, Lyttelton, Dunedin, Bluff, and Westport) for which tidal predictions are published were received in Wellington on the Bth July, 1924, from the Hydrographer to the Admiralty. The work of measuring the times and heights of high and low water was performed at the Tidal Institute, University of Liverpool. The cost of preparing the tidal predictions by the Tidal Institute permits the inclusion of another New Zealand port, for which a tide-table can be prepared on the present annual vote. The port of New Plymouth was therefore recommended, and approved by the Marine Department, and tidal predictions for that port will be given in future for 1928 and onwards. Details of the tidal work will be given in the " Records." Magnetic Observatory. The work of the Magnetic Observatory at Christchurch and the substation at Amberley has been efficiently carried on during the year by the Director, Mr. H. F. Skey, B.Sc. The magnetographs have continued in regular operation throughout the year, and the base values of the curves were determined by absolute observation of declination, dip, and horizontal force, usually taken once a month. The mean annual values of the magnetic elements as far as they are available are given in Table D following : —

Auckland. Bluff. Dunedin. Lyttelton. Wellington. j Westport. A„= 5-72ft. A 0 = 5*27ft. A.= 3-23ft. A„=3-20ft. A 0 =2-93ft. A 0 -4-77 ft. Tide Symbol. I i H. K. H. K. H. j K. H. K. H. K. H. K. _j_ I ! I L_ ! Short Period. Ft. ° Ft. ° Ft. ° Ft. ° Ft. ° Ft. 81 0-011 31-74 0-010 100-05 0-014 18-04 0-031 29-19 0-002 327-99 0-011 78-04 S2 0-580 208-31 0-502 49-79 0-248 129-20 0-172 142-28 0-101 330-48 0-959 332-22 S4 0-019 331-83 0-009 223-42 0-006 308-72 0-010 203-88 0-004 225-46 0-007 32-75 S6 0-003 41-77 0-006 170-17 0-002 112-14 0-015 342-08 0-004 307-40 0-006 331-21 Ml 0-009 144-71 0011 127-33 0-009 90-26 0-009 72-64 0-005 23-12 0-012 143-08 M2 3-818 206-37 2-858 35-68 2-466 122-25 2-884 124-74 1-608 139-02 3-747 304-43 M3 0-039 199-21 0-011 272-74 0-016 270-28 0-013 143-67 0-019 172-05 0-021 208-15 M4 0-106 124-54 0-088 226-45 0-263 177-33 0-015 82-38 0-041 250-90 0-057 53-90 M6 0-026 314-33 0-086 79-53 0-071 356-97 0-020 64-91 0-012 99-73 0-026 36-82 01 0-053 145-25 0-113 72-91 0-089 72-09 0-087 62-94 0-103 36-51 0-093 45-98 K1 0-235 169-17 0-058 115-68 0-074 91-32 0-150 82-90 0-082 85-35 0-073 184-39 K2 0-139 256-95 0-134 46-77 0-096 118-44 0-059 106-97 0-046 7-69 0-276 328-04 PI 0-077 163-91 0-023 105-44 0-024 90-54 0-052 106-11 0-032 79-01 0-022 133-91 J1 0-017 185-22 0-006 198-96 0-004 87-62 0-007 145-97 0-009 173-01 0-013 219-25 Q1 0-009 67-58 0-031 47-70 0-029 72-89 0-021 48-20 0-037 20-69 0-037 33-03 L2 0-108 219-79 0-109 32-44 0-151 104-17 0-084 162-36 0-028 149-18 0-097 285-41 N2 0-793 179-27 0-654 16-50 0-532 104-05 0-660 94-8] 0-402 104-71 0-770 289-02 V2 0-203 206-34 0-153 53-35 0-107 109-14 0-161 109-32 0-124 126-10 0-194 320-40 U2 0-102 178-49 0-065 7-93 0-029 46-15 0-097 59-03 0-065 89-62 0-134 283-83 T2 0-057 294 82 0020 89-11 0-017 242-34 0-026 228-18 0 029 274-37 0-053 9-08 (MS)4 0-173 195-31 0-081 2-78 0-108 140-60 0-102 120-36 0-035 134-93 0-105 294-78 (2SM)2 0-066 303-10 0-045 121-63 0-043 9-00 0-060 24-94 0-032 355-14 0-076 199-89 R2 0-015 211-16 0-014 111-90 0-019 220-38 0-017 143-74 0-010 116-63 0-035 178-80 Long Period. Mm 0-045 195-02 0-043 1-94 0-053 156-15 0-045 127-51 0-030 197-55 0-051 199-18 Mf 0-050 206-01 0-067 235-36 0-068 216-83 0-055 167-35 0-029 187-39 0-055 7-87 MSf 0-035 209-57 0-063 326-77 0-072 151-90 0-112 145-93 0-042 98-83 0-069 98-39 Sa 0-186 30-61 0-089 16-98 0-130 281-13 0-117 272-08 0-092 343-71 0-113 81-51 Ssa 0-071 164-94 0-115 82-05 0-067 124-63 0-107 143-78 0-078 133-80 0-116 111-03