EEPOET ON METEOKOLOGICAL OBSERVATIONS AT WISLEY. 59 



below the freezing-point on several occasions, and on the night of the 

 15th the temperature in the screen fell to 3 6° '4, and on the OTass to 

 27°'4. These cold nights did some harm to vegetation, and on Wisley 

 Common bracken shoots were killed by the ground frosts; but during 

 the latter half of the month the ground temperature did not fall below 

 40°, and on the whole the temperature was about the average for the 

 month, decreasing from about 60° over southern England to 54° in 

 North Scotland. The first half of the month was rainless, but in 

 the latter half there were several days of rain, the fall on three or four 

 occasions being sufficiently heavy to soak the ground thoroughly, and, 

 regarding the kingdom as a whole, the month was not unusually 

 dry. The amount of bright sunshine was quite up to the average, 

 and indeed in most districts above it, but whilst the southern coun- 

 ties had an average of about seven hours a day, the English Mid- 

 lands had only about six. The winds blew from most points of the 

 compass, and were frequently rather strong. 

 The results from Wisley are as follows : 



Mean temperature of the air in shade ... 59°*5 



Highest „ „ „ 83°-0 on tlie 4th 



Lowest „ „ „ 36°-4 „ 15th 



Lowest „ on the grass 27°-2 14th 



Number of nights of ground frost ... ... 4 



At 1 ft. At 2 ft. At 4 ft. 

 deep. deep. deep. 



Mean temperature of the soil at 9 a.m ... 61°-9 60°-0 57°-l 



Highest „ „ „ 65°-5 62°-l 58°-0 



Lowest „ „ „ 58°-7 58°-0 54°-l 



Mean relative humidity of the air at 9 a.m. (complete saturation being 



represented by 100) ... 70 % 



Eain fell on 11 days to the total depth of 2-02 in. 



(Equivalent to about 9| gallons of water to the square yard.) 



Heaviest fall on any day 0*68 in. on the 23rd 



The prevailing winds were from south-west to north-west, but north-easterly winds 



were experienced on several days. 

 The average velocity of the wind was 6 miles an hour. 



There were 235 hours of bright sunshine, equal to 48 per cent, of the greatest 



possible amount. 

 There were 3 days on which no sunshine was recorded. 



July. — The outstanding feature of the weather of July was the 

 prolonged drought, accompanied by exceptionally hot and sunny 

 weather, which was experienced over the greater part of the kingdom, 

 and lasted for upwards of three weeks. The hottest days occurred at 

 about the commencement of the second and fourth weeks, when 

 maximum temperatures of about 90° were recorded at several 

 places in England; at Wisley 88° was registered on the 8th, 

 and 91° on the 22nd, whilst at the Greenwich Observatory 

 on the latter date the thermometer rose to 96°. Sunshine was 

 registered at Wisley on every day of the month, the daily amounts 

 varying from four hours on the 1st to fifteen hours on the 13th, and 

 averaging eleven hours a day. For three weeks no rain fell, and 

 in many districts the total fall for the month was less than a quarter 



