SOIL AND CLIMATE. 33 



The temperatures at all the ten Punjab stations in winter 

 seem very comparable to those of date-growing regions and are 

 apparently suitable for date culture. The minimum tempera- 

 tures at none of our stations get down to 20F. (see also page 25, 

 para. 16) ; the lowest yet recorded are 23 '9F. at Rawalpindi 

 and 24 F. at Ludhiana. 



18. Regarding summer temperatures it may be noted 



that the hottest month of the season in the 



summer ^tempera- p un j a b i s June ; in Tunis and Lower Egypt it 



is July ; and in Upper Egypt and Baghdad it 



is August. Also that May approximately the beginning of the 



date fruiting season here as elsewhere is hotter in the Punjab 



than at any of the date-growing centres quoted. The Indian 



Meteorological Department have kindly given me the following 



explanation of this : 



" Northern Africa and Mesopotamia possess normal con- 

 tinental or marine climates, and the hottest part of the year is 

 accordingly the end of July or the beginning of August." 



"In that month (May) the solar heat 



is expended in heating up the dry land surface of the Punjab 

 and as the air above is prevented largely from moving away, by 

 the bordering mountains, it reaches very high temperatures. 

 On the other hand, strong and relatively cool northerly and 

 north-westerly winds prevail at that time over the north of 

 Africa and tend to keep down the temperature. There is a 

 change of wind in the autumn, the prevailing direction being 

 then south-west, and therefore a land wind with the result that 

 the months of September and October are as warm in Northern 

 Africa as those of June and May." 



The rains and cloudy weather in the Punjab in July and 

 August reduce the daily maximum temperatures here in these 

 months, and also prevent the daily minimum temperatures 

 from falling as low as they otherwise would in that part of the 

 season. 



M, DP 3 



