110 RESOURCES OF CALIFORNIA. 



accompaniment of our dry climate and clear sky, it may be 

 worth while to observe that near the ocean the clouds are rare- 

 ly picturesque or sublimely beautiful. The magnificent sun- 

 sets, where the god of light goes down amid curtains of gold 

 and crimson those high-piled banks of clouds which adorn 

 the heavens before and after thunder-showers, in the Mississippi 

 Valley are rarely seen near the coast. 



Dew is rare or slight over a great part of the State. 

 During the summer and autumn, many of the rivers sink in 

 the sand soon after leaving the mountains in which they rise ; 

 the earth is dry, arid baked hard to a depth of many inches or 

 even feet ; the grass and herbage, except near springs or on 

 swampy laud, are dried up, and as brown as the soil on which 

 they grew. 



It has been said that very hot days are less oppressive in 

 California than equal heat in the Eastern States, because the 

 cool nights serve to invigorate the system, and the extreme 

 dryness of the climate favors the evaporation of sweat, and 

 thus keeps the body cooler than in districts where the earth is 

 always moist. Evaporation is so rapid that a beefsteak hung 

 up in the air will dry before it can commence to putrefy. A 

 dead rat thrown into the street, where its body is crushed by 

 wagon-wheels so that its viscera are exposed to the air, will 

 "dry up," and its stiff hide and meat will lie during a whole 

 summer in a mummy-like condition. In many places, steel 

 may be exposed to the night air for weeks without getting a 

 touch of rust. 



It is common to ascribe the effects of the dryness of the at- 

 mosphere to the " purity" of the air ; but it is rather the ab- 

 sence of moisture. I know no reason for supposing that, apart 

 from its dryness, the air in California is purer than in any 

 other part of the continent. It may be, however, that the con- 

 stant decomposition of animal and vegetable matter lying on 

 wet ground, under a hot sun, causes the air in other States to- 

 be filled with such gases as are not set free to an equal extent 

 here. 



