THE LITERARY 



OF THE LINN^AN ASSOCIATION OP PENNSYLVANIA COLLEGE. 



Vol. hi. JULY, 1847. No. 9. 



PHILOSOPHY OF STORMS. NO. VI. 



BY PROF. W. L. ATLEE, M. D., PHILADELPHIA, PA. 



The immense force of the steam-power, generated by the condensa- 

 tion of vapor into cloud, must be apparent where, for every cubic foot 

 of water condensed from vapor in a gaseous state, the air itself, which 

 receives the latent caloric of the vapor, is nearly 7000 cubic feet lar- 

 ger in bulk, than it would have been, without having received this latent 

 caloric. This expansion of the air by means of the heat which previ- 

 ously existed in the vapor is the result of calculations, based upon es- 

 tablished principles of chemistry, which never have been contradicted. 

 The following are the data : — 



1st. The specific heat of atmospheric air is 0.° 2669. 



2d. The sensible and latent heat contained in vapor is 1212 de- 

 grees : according to Prof. Johnson 1242 degrees. * 



3d. Air is expanded 1-460 its bulk at zero, for every degree of Fah- 

 renheit to which it may be heated. 



For example : a pound of steam, at the temperature of 212°, con- 

 tains 1000*^ of caloric of elasticity, and as the sum of the latent and 

 sensible caloric of steam is the same at all temperatures, it follows, that 

 a pound of steam being condensed in 1180 lbs. of water at 32°, would 

 heat this water up one degree ; and, as the specific caloric of air is only 

 0°. 2669, if a pound of vapor should be condensed in 1 180 pounds of 

 air, it would heat that air nearly 4 degrees, or, which is the same 

 thing, it would heat 100 pounds of air about 45 degrees. And in all 

 these cases it would expand the air about 8,000 times the bulk of water 

 generated ; that is, 8,000 cubic feet for every cubic foot of water formed 

 out of the condensed vapor. And as it requires about 1,300 cubic feet 

 of vapor, at the ordinary temperatures of the atmosphere, to make one 

 cubic foot of water, if this quantity be subtracted from 8,000, it will 

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