454 THE MOUNTAIN. 



to a confirmation of Blodget's views, given in an important 

 communication to the Scientific Association, in 1853, on the 

 annual fall of rain in the United States. The showing on 

 this point now stands with the following conclusions : The 

 amount of absolute moisture or water in the air diminishes, 

 leaving the surface of the Atlantic at the foot of that plain, 

 and ascending the Appalachian steps or waves until the 

 summit range of crests is reached, where there is great 

 demonstrable decrement of humidity. After passing that 

 range, and descending into the Yalley of the Mississippi, 

 the moisture increases, until the surface of the Mississippi 

 River is reached, where the greatest amount of moisture is 

 found. A diagram of the great atmospheric sponge would 

 thus show increased and intensified shading or regular in- 

 crease of the quantity of moisture from the summit of the 

 Alleghany to the surface of both waters.* 



In Butler's " Philosophy of the Weather"f we have the fol- 

 lowing statements, made from facts furnished by Blodget : 



" The northern portion of the continent lies beneath the zone of 

 extra-tropical rains, and north of the northern limit of the northeast 

 trades is never uncovered from it, and has no distinct rainy or dry 

 season, although more rain falls at certain periods, and in certain 

 localities, than at others. The climate of that part of Oregon which 

 lies upon the Pacific, and the character of its rains, resemble those 

 of Northwestern Europe, and will be further explained hereafter. 



" Coming to the portion of the continent which we occupy, the 

 United States, we find it diiferent, still a most favored region. Por- 

 tions of it, Eastern Texas, for instance, are upon the same parallels 



with a regular set of meteorological instruments. It is hoped, however, that this 

 much-desired object will soon be achieved, when results of the highest interest and 

 significance may be expected. Located on the rim, or eastern margin of the great 

 continental basin, and some 2000 feet above the sea, it is inevitable that results highly 

 important to science must be accomplished. 



* One cause of the general impression that more water falls on the Alleghany than 

 east or west is, that during the winter months the mountain summits are generally 

 white with snow, while there is no snow at eastern or western base or the sides of the 

 mountain. Of course, the height of the mountain, stretching up into colder spaces, 

 and preventing the melting of the snow, will explain this, without any increase in 

 the quantity of water falling in the form of snow. 



f This is an interesting and suggestive book, and one of the best contributions made 

 recently to the science of meteorology. 



