PNEUMATICS. 



mid atmosphere, and from the second the preva- 

 lence of winds of different temperatures. 



When the rain exceeds 25 inches a-year, the climate 

 is to be accounted moist. In the year 1809, the 

 rain that fell at Dalkeith, near Edinburgh, was 

 28.5 ; at Glasgow 25.1 ; at Largs, at the mouth of 

 the Clyde, 40.6; and at Gordon Castle, on the 

 east coast of Scotland, 24.5: At London, in the 

 same year, 20.7 ; in the preceding year, the fall 

 was but 18.8. In some places of this island, such 

 as Kendal and Keswick, the rain amounts to 64 

 and 68 inches in a year. 



434. The disposition of the rocks in strata, con- 

 tributes much to the collecting of the waters un- 

 der the surface, and the Conveying them without 

 waste, as if in close pipes, till they are united in 

 fountains, lakes, rivers, &c. 



BERNARD PALLASSY seems to have been the first who 

 made this remark ; he even brought it to the test 

 of experiment. 



435. The region of the air in which the preci- 

 pitation of humidity takes place, is one where the 

 temperature is frequently below freezing ; the fro- 

 zen particles then uniting, as in the case of melt- 

 ed vapour, form flakes of Snow, which reach the 

 ground in that state, when the cold of freezing con- 

 tinues down to the surface. 



VOL. I. X When 



