A.—4

were classified as follows : 232 instrumental, of local origin and very feeble ; 44 local, not reported felt; 10 local, reported felt ; 58 epicentres within 1,000 km. almost all from Tongan Deep ; 22 epicentres more than 1,000 km. distant. Radio reports of earthquakes were sent to the New Zealand Government Seismologist; monthly reports to Professor H. 11. Turner, President, Seismological Section of the International Union of Geodesy and Geophysics, and to several prominent seismologic observatories. A complete report for the period July, 1923, to December, 1924, with a determination of the epicentres of the larger earthquakes occurring in the Pacific, was prepared [for publication, and sent to the Honorary Board of Advice, New Zealand, for printing. Meteorology. During 1924 continuous records were obtained of temperature, barometic pressure, rainfall, humidity, and sunshine. The extreme high and low values of the temperature and pressure during each month, with the mean humidity and rainfall, are given in the following table : —

Ten co-operating stations have been established on the Island of Upolu and the adjacent Island of Savai'i. These are located on plantations, and, due to changes in personnel, interruptions in the service have occasionally occurred; yet as the ownership of the plantations gradually becomes more permanently settled the reports will improve in standardization. It is hoped that steps will be taken to co-ordinate the efforts of the various meteorological observers in the South Pacific Ocean — the year Apia Observatory has urged that this be done. In the enormous area included between the Equator and the Tropic of Capricorn and the meridian of 140° W and 160° E, there are at present fifteen stations regularly reporting weather conditions. But these reports are not all sent to the same destination ; seven go to the British Meteorological Office, three to the Meteorological Branch of the Marine Department, New Zealand, and seven to the Australian Commonwealth Bureau of Meteorology. A few stations send reports to more than one office. There are also scattered and unclassified returns from business organizations and missionary societies. Recent developments in analytic world meteorology indicate the probability of more nearly accurate long-time forecasting, provided all obtainable data are assembled on a single weather map. A determined effort has therefore been made to centralize the observing stations and to make the summarizing of conditions reported and the deductions resulting from them collectively more accessible to all concerned. Complete details of the meteorological elements are published in the annual report of the Observatory : the report for 1923 in is the Press. In view of the unavoidable delay in making available to the world the meteorological data collected it was deemed advisable to issue, beginning January, 1925, a monthly summary to be sent to those investigators and institutions, both scientific and commercial, that have immediate use for weather information. About forty copies per month are distributed. A fundamental investigation of atmospheric tides has been initiated at the instigation of Professor S. Chapman, F.R.S., with the aid of a grant from the Royal Society. Dr. Wagner had reported the components of atmospheric tides at Apia and at Batavia, basing his deductions on observations made from 1903 to 1906. As regards Batavia, later Dutch investigators subsequently deduced values only one-third of those given by Dr. Wagner. In view of the importance of the subject not only in meteorology but in magnetism and atmospheric electricity, the investigations as regards Apia has been taken up again, using the data from 1914 to 1924, and a different method of mathematical analysis. Solar Radiation—A research has been undertaken on solar radiation, employing the Moll thermopile and the Richard recording millivoltmeter to measure the intensity of the radiation. The

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Temperature, Extreme. Barometer, Extreme. Month. 1 j Humidity. Rainfall. High. Low. i High. I Low. I I F°. F°. Inches. Inches. Per Cent. Inches. January .. .. .. 88-7 72-9 29-97 29-54 85-30 17-70 February .. .. .. 90-1 72-0 29-94 29-68 85-33 14-06 March .. 89-8 72-9 29-93 29-74 83-12 10-06 April .. 88-7 72-0 29-94 29-69 83-10 8-30 May .. 88-9 72-1 29-97 29-76 83-97 5-82 •Tune .. 88-3 71-4 30-03 29-80 81-87 10-05 July 86-4 70-5 30-00 29-78 85-84 9-61 August .. .. 86-5 70-9 30-02 29-79 84-29 5-35 September .. .. .. 88-9 68-9 30-04 29-80 81-63 3-82 October .. .. .. 88-5 70-5 30-02 29-76 81-58 8-08 November .. 88-3 71-8 29-94 29-72 84-23 10-24 December .. .. .. 88-2 72-9 29-92 29-59 83-45 15-91 Mean and total .. .. .. .. .. .. 83-64 I 119-00 I I I