82 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



reduced the temperature near the ground sufficiently to damage 



bracken, French beans, vegetable marrows, and other tender plants. 



The following table summarizes the Wisley observations : — 



Mean temperature of the air in shade . . . .59-1° 



Highest ,, ,, 85 0 on the 30th 



Lowest „ „ „ . 39° „ 8th 



Lowest ,, on the grass ..... 29 0 8th 



Number of nights of ground frost ........ 2 



At depth of 

 1 ft. 2 ft. 4 ft. 



Mean temperature of the soil at 9 a.m. . . . 59*8° 58-0° 54' 9° 

 Highest „ „„„... 66° 63 0 58 0 

 Lowest „ „ „ 55° 55° 53° 



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

 sented by 100), 70 per cent. 



Rain fell on 10 days, to the total depth of 0-77 in. (equivalent to about 3^ 

 gallons of water to the square yard). Heaviest fall on any day 020 in., on the 

 7th. 



The prevailing winds were from north-east and south-west. 

 The average velocity of the wind was 3 miles an hour. 



There were 259 hours of bright sunshine, equal to 53 per cent, of the greatest 

 possible amount. 



There were no days on which sunshine was not recorded. 



July. — The exceptional heat which marked the closing days of June 

 continued into July, and the opening of the month was characterized by 

 the quite unusual temperature of 90 degrees at Wisley ; and although 

 such tropical conditions did not continue, yet fairly warm weather pre- 

 vailed until the last week, when, under the influence of a more or less 

 northerly air-current, it became decidedly cool for the middle of summer. 

 The mean temperature for the month, at Wisley, was only half a degree 

 below the average, and therefore, from the horticulturist's or agri- 

 culturist's point of view, the month was satisfactory as regards warmth. 

 The rainfall also was only slightly in excess of the normal, and although 

 a good many thunderstorms occurred in different parts of the kingdom, 

 none of them was of exceptional severity. Bright sunshine was, 

 however, somewhat deficient in many districts, and at Wisley it aver- 

 aged only five and a half hours a day ; but many days were prac- 

 tically sunless, and the general character of the month was decidedly 

 cloudy and changeable. 



The Wisley results are as follows : — 



Mean temperature of the air in shade . . . 61 • 8° 



Highest „ „ ,, ,, .... 90 0 on the 1st 



Lowest „ „ „„.... 43 0 „ 29th 



Lowest „ on the grass . . . . .35° „ 30th 



Number of nights of ground frost ....... None 



At depth of 

 1 ft. 2 ft. 4 ft. 



Mean temperature of the soil at 9 a.m. . . . 64 0 63 0 6o° 



Highest „ „ „ 6b° 65 0 6i° 



Lowest „ „ „ 6o° 6i° 58 0 



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

 sented by 100), 75 per cent. 



Rain fell on 13 days, to the total depth of 1-90 in. (equivalent to about 9 

 gallons of water to the square yard) . Heaviest fall on any day 0-57 in., on the I2th» 



The prevailing winds were from south-west and west. 



The average velocity of the wind was 4! miles per hour. 



There were 174 hours of bright sunshine, equal to 35 per cent, of the greatest 

 possible amount. 



There was one day on which no sunshine was recorded. 



