METEOROLOGICAL OBSERVATIONS AT WISLEY, 1916. IOI 
During the last week, however, the heat and drought combined caused 
vegetation to suffer considerably. 
\ The results of the daily meteorological observations are summarized 
in the following table : 
Mean temperature of the air in shade . . . .60 3° 
Highest „ „ „ 
Lowest „ ,, ,, 
„ „ on the grass 
Number of nights of ground frost . 
83' 
35 ( 
on the 30th 
„ 2nd 
15th 
None 
Mean temperature of the soil at 9 a.m. 
Highest „ „ „ 
Lowest „ 
1 ft. 
597 
63° 
58° 
At depth of 
2 ft. 
' 58-3° 
6l° 
57° 
4 ft. 
55-8 
58° 
55° 
Mean relative humidity of the air at 9 a.m. (complete saturation being repre- 
sented by 100), 78 per cent. 
Rain fell on 8 days, to the total depth of 0 80 in. (equivalent to about 3 J 
gallons of water to the square yard). Heaviest fall on any day 0-34 in., on the 
6th. 
The prevailing winds were from between south-west and north-west. 
The average velocity of the wind was 4 miles an hour. 
There were 171 hours of bright sunshine, equal to 35 per cent, of the greatest 
possible amount. 
There were 4 days on which no sunshine was recorded. 
August. — The dry weather of the latter part of July was prolonged 
throughout the first half of August, by which time rain had everywhere 
become badly needed, since there had been a continuous succession of 
bright, hot days, on many of which the temperature had exceeded 80 °, 
lasting for nearly four weeks. This drought was now followed by a 
spell of unsettled rainy weather, lasting till the close of the month, by 
which time the fall of rain had everywhere exceeded the usual amount 
for the entire month, and in some districts the excess was very con- 
siderable. Quite at the close of the month there was a very heavy and 
prolonged downpour over a great part of south-western England, 
which resulted in falls of between three and four inches in less than 
twenty-four hours. The temperature during this latter half of August, 
notwithstanding the rain, differed very little from the normal, so that, 
taking the entire month, the mean temperature was two degrees in 
excess of the average ; and regarding its weather generally, from a 
gardener's point of view, it was a very satisfactory month. 
The observations made at the climatological station at Wisley 
give the following results : 
Mean temperature of the air in shade 
Highest „ „ 
Lowest ,, 
Lowest ,, on the grass 
Number of nights of ground frost . 
Mean temperature of the soil at 9 a.m 
Highest 
Lowest 
634° 
83-4° 
44i° o 
352° 
on the 1st 
3ist 
5th 
none 
1 ft. 
62-8* 
65° 
59° 
At depth of 
2 ft. 
6i'7 
63° 
6i° 
4 ft 
59'2 C 
6o° 
58° 
Mean relative humidity of the air at 9 a.m. (complete saturation being repre- 
sented by 100), 78 per cent. 
Rain fell on 15 days, to the total depth of 3-23 in. (equivalent to about 15 
