METEOROLOGICAL OBSERVATIONS MADE AT CHISWICK IN 1900. 355 
May.' — Cold and very dry. The days were, as a rule, about 1 degree 
colder than is seasonable, while the nights were of about average 
temperature. On the coldest night the thermometer on the grass showed 
10 degrees of frost. 
The rainfall was very light, being not much more than half the 
average quantity for the month. 
Mean temperature of the air in shade 
o2°.0 
Highest 
70°.2 on the 27th 
Lowest 
33°.3 
„ 16th 
Lowest temperature on the grass ... 
22°.l 
„ 16th 
At 1 ft. 
At 2 ft. 
At 4 ft. 
deep. 
deep. 
deep. 
Mean temperature of the soil at 9 a.m. 
53°.3 
51°.8 
49°.7 
Highest 
58°.2 
55°.l 
51°.8 
Lowest 
49°.5 
48°.4 
47°.8 
Mean relative humidity of the air at 9 a.m. (complete saturation being 
represented by 100) 69 
Rain fell on 11 days to the total depth of 1-12 in. 
(Equivalent to about 5 gallons on each square yard of surface in the Gardens.) 
Heaviest fall on any day 0*23 in. on the 24th. 
June. — Warm, with average rainfall. The days were, as a rule, about 
1 degree warmer, and the nights about 2 degrees warmer, than is season- 
able. On the coldest night the thermometer on the grass fell to 
86 degrees, or 4 degrees short of the freezing-point. 
The rainfall was about the average quantity for the month. 
Mean temperature of the air in shade 60°. 1 
Highest 86°.4 on the 11th 
Lowest 43°.9 „ 27th 
Lowest temperature on the grass .. ... ... ... ... 36°.2 ,, 14th 
At 1 ft. At 2 ft. At 4 ft. 
deep. deep. deep. 
Mean temperature of the soil at 9 a.m 60°.7 58°.l 54°.4 
Highest 64°.9 60°.2 56°.l 
Lowest 53°.0 54M 51°.9 
Mean relative humidity of the air at 9 a.m. (complete saturation being 
represented by 100) 72 
Rain fell on 13 days to the total depth of ... ... .. ... 1*90 in. 
(Equivalent to about 9 gallons on each square yard of surface in the Gardens.) 
Heaviest fall on any day ... ... ... ... 0*33 in. on the 21st and 25th. 
July. — Most exceptionally warm and very dry. The days were, as a 
rule, about 7 degrees warmer, and the nights about 3 degrees warmer, 
than is seasonable. On the coldest night the thermometer on the grass 
fell to 33 degrees, or 1 degree short of the freezing-point. 
The rainfall was very light, being less than half the average quantity 
for the month. 
Mean temperature of the air in shade 
66°.9 
Highest 
91°.7 
on the 25th 
Lowest 
42°.2 
8th 
Lowest temperature on the grass ... 
33°.l 
8th 
At 1 ft. 
At 2 ft. 
At 4 ft. 
deep. 
deep. 
dee]). 
Mean temperature of the soil at 9 a.m. ... 
67°.4 
63°.4 
58°.6 
Highest 
73°.5 
67°.3 
61^3 
Lowest 
61°.5 
59°.5 
56°.l 
M 
