126 



JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



total considerably exceeding 100 hours, and even London recording 64 

 hours, which is 20 hours more than the usual amount for the month. 

 The results of the observations made at Wisley are as follow : — 



Mean temperature of the air in shade 42°.2 



Highest „ „ „ 540.0 on the 17th 



Lowest „ „ „ 28°.0 „ 9th 



Lowest ,, on the grass 21°.0 9th 



Jan. 







Afin 



May 



Tune. 









Or/,. 





























-h 















rat 











4- 

























4- 





































A 









































-em 













r 























V 

































i 



































































ICLi 



nfck 



11 









nun 



1 













1 

























i 











f/M 



'//M 





i 



////// 



1 









L 



'/////// 



m 







1 

































o 



5L« 



o 



Fig. 64.— Differences of the Monthly Means of Temperature and Rainfall 



from the average. 





At 1 ft. 



At 2 ft. 



At 4 ft. 





deep. 



deep. 



deep. 



Mean temperature of the soil at 9 a.m 



39°.8 



41°.0 



41°.9 



Highest „ „ „ ... . 



43°.6 



43°.2 



43M 



Lowest ,, „ „ ... . 



35°.3 



37°.5 



40°.6 



Number of nights of ground frost 







10 



Mean relative humidity of the air at 9 a.m. 



(complete saturation being 





represented by 100) f' 







87% 



