CHAMBERS'S INFORMATION FOR THE PEOPLE, 

 called isothermals (Gr t'sos, equal, thernie. heat), I when they mark mean annual temperature ; 



30 go so 120 iso ~_jao 



zgo__ 90 'i*j__ 30 *Q 60 30 



Fig. i. 



isotherals (Gr. theros, summer), when they mark I the hottest month, July ; and isockeimals, or iso- 

 either the mean of the summer months or that of I chimenals (Gr. cheima or chima, winter), in regard 



Fig. 2. 



to winter. Fig. . I is such a chart, exhibiting the while fig. 2 exhibits the hottest and coldest 

 distribution of the mean annual temperature ; months ; the dotted lines marking the mean 



42 



