TEMPERATURE. 145 



times as mild as 41 0< 1, and sometimes as cold as 25*7; July, 

 the hottest month, is also more variable than the average, being 

 sometimes as hot as 69'5, and again as cold as 58'0. The 

 average difference between January and July is 27'2, which does 

 not differ much from the results of this kind obtained in the 

 vicinity of London, and generally on the eastern side of the island, 

 at points removed from the immediate influence of the sea air. 



On the western side of the island, January and July are still 

 the months most contrasted in temperature, but the difference 

 between them is reduced, the former being warmer by about 2 

 until we reach the latitude of Kendal. Here the temperature 

 of January sinks nearly to that of York, and the heat of July 

 is about 4 less. The mean temperature of the year is attained 

 at York, on the average, a little after the middle of April and a 

 little before the middle of October ; the day of greatest cold is 

 on the average the 18th of January, and the hottest day on the 

 average the 18th of July. 



The trying month of April appears to be warmer at York than 

 at most places on the eastern or western sides of England north 

 of London and Gloucester; March and May are also a little 

 warmer than in most other places circumstances by no means 

 to be forgotten among the favourable points of its local climate. 

 In fact, at this period, the easterly and north-easterly winds 

 which prevail over the island, and are very distressing on the 

 eastern coasts, appear to be somewhat mitigated or diverted 

 from a direct course over York by the wolds and moorlands 

 which rise between the Vale of the Ouse and the sea. 



The average temperature of any one month at York corre- 

 sponds almost exactly to a calculated number proportioned to 

 the meridian altitude attained by the sun, not on the middle day 

 of the month, but on a day about twenty-five days earlier. 



This agreement is so remarkable as to justify for York the 

 claim of regular climate, or climate due to the latitude, the tem- 

 perature moving with, or rather in consequence of the heating 

 power exerted by the sun. 



