RAIN AND SNOW 



99 



to respond to it so quickly as those on the lawns 

 and fields out of town. This may be imagination 

 with the observer, and yet it is well known that 

 the rain which falls in the city is not the same 

 rain as that which falls in the country, though 

 both precipitations may come from the one 

 cloud. City rain is fouled by passing through 

 smoke, dust, and gases. It gathers sulphuric 

 acid, which corrodes metal, paint, and iron, and 

 certainly does not help vegetation. The coun- 

 try rain is always purer because falling through 

 a clearer air. 



Precipitation from the clouds usually takes 

 the form of rain and hail in the summer, sleet 

 in the spring, and snow or frozen ice-crystals in 

 the winter. They are all easy to account for as 

 regards their forms except hail, which is frozen 

 rain perhaps, but a satisfactory explanation of 

 how it is formed and frozen has not yet been 

 offered. Hail falls in hot, sultry weather and 

 with a thunder-storm. For that reason it is sus- 

 pected that it has to do with electricity or is 

 caused by it. It would seem at first blush as 

 though those heavy drops of rain, which have 

 been spoken of as the first to fall from the thun- 

 der-cloud, were sometimes congealed to ice and 

 united to other drops in the congealing proc- 



