ATMOSPHERIC OBSERVATIONS. 399 



again in fog, or in rain, when the atmosphere cools ; 

 and thus a constant visible intelligence is going on. 

 How much insensible intercourse takes place we 

 know not, but we can comprehend its agency by 

 the effects and events that manifest themselves. 

 Our country people think these " rokings" (reek- 

 ings) of the earth greatly favourable to the growth 

 of vegetation, supposing it occasioned by the internal 

 heat of the earth producing a vapour like that from 

 fermenting soil, thus warming the roots ; but if the 

 theory be defective, the fact may be true, by the 

 caloric in the sun's rays promoting the decompo- 

 sition of the water, or separating the component 

 parts (oxygen and hydrogen), which uniting with 

 other matters contained in the earth arid atmosphere 

 (carbon and carbonic acid) become by this means 

 the basis of all our fruits, our sweets, our sours, 

 resins, &c., in the vegetable world ; and hence there 

 is a constant decomposition of water going forward 

 by these alternations, and a constant formation of 

 matters beneficial and necessary for the various in- 

 habitants of the earth. When we perceive that a 

 shower of rain has revived or promoted the increase 

 of vegetation, we must understand, that the mere 

 wetting it has not accomplished this ; but that the 

 vegetable has by means of its foliage, aided by light 

 and heat, decomposed or separated the combined 

 matters of the water, and taken from it certain 

 portions as essential to its vigour, or been re-vie- 



