DEW. 1:23 



::i:iin, however, that with f ;ions, it is 



only on calm and clear evenings that dew is formed, and the 

 warni'T i!i. daj li.is b'/en, tlie greater is the amount of deposi- 

 tion. It is evident, therefore, that some part of the material 

 necessary is derived from the upp-r ;i ; and as dew 



is found principally beside vegetation, th: other material 

 comes from it. 



What then is dew 1 Dew is water, and it is formed in a 

 similar /un,tn<r, by a reciprocal or chemical action between the 

 two c' matter, viz: the vegetable emnn'iliuns or gases 



rising from plants, and reciprocating with that from the upper 

 mineral afmo.yhcre, which on a calm evening descends and 

 meets it. 



If the sky is cloudy, the same action is going on in forming 

 the cloud, and making the cloud larger, therefore it cannot 

 work on the earth's surface ; and if it is windy, the gases take of 

 necessity a horizontal direction, and do not meet in a suitable 

 position to form dew, for each class is blown onwards at its own 

 level, forming cloud. 



Sometimes the differing gases will be more dense, and meet in 

 the lower atmosphere, the result is a fog ; and if the cold 

 mineral air is mure powerful, the result is hoar frost. On the 

 latter occasi< >n. i f a rounded stone or stick be examined, it will be 

 observed that the spears of ice are longest at the highest points 

 of the surface, and that they diminish on the sides, till they 

 degenerate into a mere glistening powdered dust. Thus show- 

 ing, in a humble way, the direct continuity in the action of atoms, 

 before spoken of, and that the formation is caused by a direct 

 reciprocation between the ascending, and the descending gases. 



