Mean Monthly Temperature and Relative Humidity in the Underground Chamber and in the Open Air during the year 1930.
Month 1930. In Underground Chamber, In the Open Air. Excess of Underground Chamber over Open Air. Temperature Relative Humidity Temperature Relative Humidity Temperature Relative Humidity January, 70.8 84 54.6 60.3 +16.2 +23.7 February 68.5 80 60.3 73 +8.2 +7 March, 69.6 84 63.9 74 +5.7 +10 April, 74.1 94 73.5 79 +0.6 +15 May, 75.4 96 79.2 81 -3.8 +15 June. 77.5 96 81.9 83 -4.4 +13 July. 79.2 96 82.3 83 -3.1 +13 August. 80.1 95 82.1 83 -2.0 +12 September 79.8 94 80.7 79 -0.9 +15 October, 78.6 90 76.8 73 +1.8 +17 November, 77.8 88 70.7 64 +7.1 +24 December, 75.4 84 64.0 60 +11.4 +24 Range, 11.6 16 27.7 23II. METEOROLOGICAL INSTRUMENTS.
All the meteorological instruments were maintained in good order throughout the year.
The thermometers in use were compared with Standard No. 647 in summer and winter.
The working of the electric hammer on the Nakamura Pluviograph was tested daily at 11h.
The Beckley and Dines Baxendell Anemographs were oiled and the orientation of the vanes was checked once a month. The Dines Baxendell instrument continues to work satisfactorily, except at very low velocities when its action is uncertain.
The bearings and helix of the Beckley Anemograph were renewed in July.