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Atmospheric Electricity . Lhe measurement of potential gradient, using a Benndorf electrometer, was continued, as in former years, under the guidance of the Carnegie Institution of Washington, which provides a grant-in-aid for this purpose. The reduction factor was checked from tifne to time by absolute observations on the sandflats to the south of the Observatory. I he mean values of the potential gradient at Apia during 1938, expressed in volts per metre, are as follows : January, 128 ; February, — (no days of character, 0) ; March, 123 ; April, 118 ; May, 103; June, 132; July, 140; August, 139; September, 111; October, 102; November, 102; December, 138. 1 hese figures refer to days during which no negative potential occurred. Time Service. The " Synchronome " clock, which provides the time marks for the seismographs and magnetographs, was controlled by comparisons with the standard clock, Strasser and Rohde No. 381. The latter was checked regularly by wireless time signals from Honolulu, San Francisco, and Saigon. Tides. The tide-gauge at the Lagoon House remained in operation until November, 1938, when the clock became erratic. It was sent to America for repairs, and has not been returned yet. Buildings. A new building, including a workshop, balloon room, and two other small rooms, was completed in February, 1939. Staff. lhe Director, Mr. J. Wadsworth, resigned on 9th June, 1939, and Mr. H. B. Sapsford was appointed as Acting-Director.

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