348 Sir D. Brewster on the Law of Daily Temperature. 



of latitude in producing an approximation to a continental 

 climate. The mornings at Inverness, from 1 h. a.m. till about 

 5 h. 20 m. a.m., are colder ; and the days, from 9 h. a.m. till 

 3^ h. p.m., are warmer in reference to the mean temperature 

 than those at Leith ; whereas, about the time of the morning 

 and evening mean temperatures, it is warmer at Inverness in 

 the morning and colder in the evening. 



Having obtained the ordinates of the mean annual curve of 

 the daily temperatures, it becomes a curious subject of inquiry 

 if this curve has any resemblance to curves with which we are 

 familiar. With this view we must divide it into four portions 

 or branches, namely, that between the hours of the evening 

 mean temperature and the minimum ordinate ; that between 

 the minimum ordinate and the morning mean ; that between 

 the morning mean and the maximum ordinate ; and that be- 

 tween the maximum ordinate and the evening mean. In this 

 way the mean annual curve of daily temperature will be di- 

 vided into four different curves, which have a striking simi- 

 larity to parabolas, as shown by the following table, which 

 contains the mean annual hourly temperatures for 1824 and 

 1825, as observed, and as calculated on the supposition of the 

 temperatures being the abscissas of parabolas, and the horary 

 intervals the ordinates. 



