ISO JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



Fig. 3S exhibits the monthly march of the temperature of the air, and 

 fig. 39 that of the soil compared with the mean temperature of the air. 

 From the latter diagram, it will be seen that the temperature of the soil 





Jan 



Feb 



^AS 



Apr 



May June 



July 







Oct Nov 



Dec 





7D 



























70 



• 



S 





























Rd 













h 















Rh 



s ! 











i — 

 — i 



f 



I 



> 



\ 











5 



50 











L 



■ 







. — — 



\ 







fiO 



• 



S 







f 



4 



J 















; 







40 







f 

















• 



K 



40 



• 



S 











- « - 1 



T£MP. Of AIR 



• ] A SOIL 



IF! 

 2 • 



D££P 





5 



5D 



















^4—- 









30 



Fig 39.— Meax Temperature of the Soil at 9 ajl, at a Depth of 1 Foot, 

 2 Feet. axi» 4 Feet below the Surface compared with the Hjbap 

 Temperature of the Air. 



at depths of 1 fost and 2 feet follows very closely the monthly march of 

 the mean temperature of the air up to July, but throughout the later 

 months the soil, parting with its heat less rapidly than it absorbed it, 

 remained warmer than the air till the close of the year. 



