F 2
Kew Thermograph.-This instrument, which was set up in the new thermometer shed in January 1914, was dismounted in the month of April. The clock stopped frequently, and on examination was found to be badly rusted. It is not designed for an open exposure. It is proposed to substitute a Richard hygrograph.
Thermometers. All thermometers in use were compared with the Kew Standard in winter and summer.
The following table shows the results of comparisons between the Kew standard purchased in 1884 and a Griffin Standard of Jena Normal Glass purchased in 1914. When compared with the National Physical Laboratory Standard, in April 1914, this thermometer required a correction of 0°.09F, which has been duly applied:
Date. Kew Standard 647 Griffin 29996 (corrected). K-G 1914 July 2, 81.82 81.72 +0.10 1915 January 19, 60.00 59.86 +0.14 1915 September 29, 90.00 89.93 +0.07The results indicate that the Kew Standard No. 647 reads 0°.10 too high—a very small change in thirty years.
III. METEOROLOGICAL OBSERVATIONS AT THE OBSERVATORY.
Continuous photographic records showing the variations of barometric pressure and temperature, dry and wet bulb, were obtained with Kew pattern instruments, and automatic records of the direction and velocity of the wind with a Beckley and a Dines-Baxendell anemograph, modified as described in the Report of 1912. The amount of rain is recorded automatically by a Beckley and a Nakamura pluviograph, the amount of sunshine by a Campbell-Stokes universal sunshine recorder, and the relative humidity of the air by a small Richard hair hygrograph.
Eye observations of barometric pressure, temperature of the air and of evaporation were made at each hour of Hongkong Standard time. (Until the end of the year 1912 they were made at each hour of Hongkong Local time.) The character and direction of motion of the clouds were observed every three hours. Daily readings were taken of self-registering maximum and minimum thermometers.
Principal Features of the Weather in 1915. The principal features of the weather in 1915 were the absence of typhoons till the autumn, high temperature, low wind velocity, and large variations of pressure above and below normal. The seasonal distribution of rainfall was somewhat abnormal, being moderately in defect in April, June, August, and September, and considerably in excess in October.
* Until April.