F 15
In the following table is given the excess of the observed over the computed error after cloudy periods during 1923 :--
Date 1923. Interval without observations. Excess of observed over computed error. January 3 2 days + 0.02 25 15 0'45 15 4 + 0.20 22 3 + 0.29 25 2 + 0.04 February 15 72 + 0.04 23 28 0.36 28 6 + 0.24 March ** + 0·03 April "" 0°09 May 11 16 + 0.15 20 22 + 0'27 22 4 +- 025 22 2 + 0.14 TUI COG NW W W OW N NaN W + 0·09 ARKALAR R R R R R + 0.35 יי ΟΤΙ June 4 3 + 0.53 15 ** + 0.11 27 15 4 "" 3 July 17 5 3 6 24 51 3 5 24 27 24 99 3 31 4 3 27 31 2 31 *2 55 + 0.39 August 6 2 + 0.24 14 20 10 - 0·95 20 94 *1 September * October 23 November 16 26 0'49 26 31 0.62 December +0.56 3 N W į 15 2 0'27 16 15 2 31 ༣ + 0.27 10 2 *1 0'33 2 NEN N N N N N 0*18 7 3 99 4 2 0'42 17 + 0.18The Dent Mean Time clock (No. 39740) was used throughout the year for dropping the Time Ball, maintaining the electric time service in the Observatory, and sending hourly signals to the Railway, the Post Office, the Telephone Co., and the Eastern Extension Telegraph Co. The clock is corrected daily before 10 a.m. and before 4 p.m. by the electric regulating apparatus. The daily rate of the pendulum is kept below 0'5 sec. by the addition or removal of weights.
Chronometer Dent No. 40917 is on loan to the Stonecutters Radio Station.
Batteries, Power Supply, &c.-The necessary current for the Time Service has been supplied by accumulator batteries, charged as found necessary from the alternating mains of the China Light