THE CLIMATE OF GREAT BRITAIN. 265 



climate of Great Britain, but geographically interesting. 

 In examining the polar presentation of the London 



FIG. 2. 



Northern hemisphere on an equal-surface projection, showing curves of 

 mean annual and midsummer temperature through London. 



isotherm, we see that in two parts of its course it 

 exhibits a tendency to travel northwards, and becomes, 

 in fact, convex towards the pole. If we laid down iso 

 therms of greater mean temperature that is, nearer 

 the equator we should find this peculiarity gradually 

 diminishing. But if we laid down isotherms of lower 

 mean temperature, we should find the convexities 

 gradually becoming sharper and more defined, approach- 



