REPORT OF THE METK()ROLOGl!<T. 263 



would settle to the bottom as fast as they formed, all our lakes 

 and rivers aud niueli of the ocean would freeze solid from bot- 

 tom upwaixls, and, once frozen, would only melt a little at 

 the top during the warmer months of the year, to be again 

 quickl}^ frozen solid when the cold nights of autumn returned. 



4th. AVater has great specific heat, the greatest of all known 

 substances; that is, it re(iuires more heat to raise a pound of 

 water one degree in temperature than it does for any other 

 substiince; and conversely, the cooling of water requires it to 

 yield up a corresponding amount of heat energy. Hence lakes 

 and oceans heat and cool but slowly, thereby greatly moder- 

 ating the climate of adjacent lands. The Great Lake region, 

 although much farther north than Nebraska, aud its average 

 temperature considerably lower, is a fruit-gTOwing district 

 because its extremes of temperature are almost never great. 



5th. Water has great latent heat of vaporization. It takes 

 966 times as much heat to vaporize a mass of water, that is, 

 to change it from water at 212 degrees Fahr. to vapor at 212 

 degrees as it does to raise it from 211 degrees to 212 degrees. 

 Hence evaporation keeps temperature down even much more 

 than the mere presence of water does. Conversely, the con- 

 densation of water vapor into water requires the surrender 

 of an equally large amount of heat ; otherwise rain would fall 

 in torrents over and near the ocean, but would rarely get very 

 far from it. Even as it is, our inland position gives us none 

 too large a share of the world's rainfall. 



6th. Water has great latent heat of melting. It requires 

 143 times as much heat to change it from ice at 32 degrees 

 Fahr. to water at 32 degi'ees as it does to raise it from 32 de- 

 grees to 33 degrees, ()tller^^'ise ice on every warm winter day 

 would melt almost instantaneously and would rush away in 

 torrents. 



In view of these six facts it is not too much to say that if 

 our chief fluid on th(^ earth were not water, our weather would 

 be a series of catastrophes. 



It is in view of facts lik(^ these that the problems of agri- 



