170 THE WEATHER, AND WEATHER PROPHETS. 



must, one would think, manifest itself in some effect 01 

 other on our weather and climates. Such, however, 

 does not yet appear to be the case. The most obvious 

 consequence would seem to be a periodical return of 

 hot and cold years, which, however, the average regis- 

 tered temperatures of successive years in different places 

 have not borne out. Yet, after all, it is possible that 

 meteorologists may here have been on a wrong scent, 

 and that increased emission of heat from the sun may 

 make itself felt, not so much in any material increase 

 of the average annual temperature, as in an increased 

 generation of vapour from the ocean ; in a much more 

 copious and immediate rainfall in the equatorial regions 

 of the globe, and in a sensible increase of it over the 

 whole earth's surface : but especially in a more cloudy 

 state of the general atmosphere, consequent on the intro- 

 duction of a larger amount of vapour into it ; and in an 

 increased tendency to atmospheric disturbance and bar- 

 ometric fluctuation. No one who has watched with dis- 

 appointment the rapid upcast of cloud on a calm morn- 

 ing commencing with unclouded sunshine, which blots 

 the prospect of a glorious summer day, and who has 

 seen the same change take place day after day, often for 

 weeks in succession, can have failed to be struck by that 

 self-induced interposition of a veil between the sun and 

 the earth's surface which mitigates the ardour of his 

 beams and tempers them to the requirements of animal 

 and vegetable life. The increased heat, or by far the 

 greater part of it, may be expended in re-evaporating tht 

 upper surface of this very cloud, and, by so doing, simply 



