Mr. D ALTON on the constitution of the atmosphere. 185 



sufficient reason, then the height of the azotic atmosphere 

 will be only 44 miles. The very fine and attenuated carbonic 

 acid atmosphere must ascend to the height of 10 miles, if a 

 full atmosphere of this gas ascend to 30 miles ; and that of 

 steam or aqueous vapour to the height of 50 miles, allowing 

 the specific gravity of steam to be .625, and the weight of 

 its atom to be 8. 



It may be worth while to contrast this view of the consti- 

 tution of the atmosphere with the only other one, as far as I 

 know, that has been entertained. 



According to one view. 

 1. The volumes of each gas 

 found at the surface of the earth 

 are proportional to the whole 

 weights of the respective atmo- 

 spheres. 



Weight of 

 atmosphere. 



101.43 



According to the other view. 



1. The volume of each gas 

 found at the surface of the 

 earth multiplied by its specific 

 gravity J is proportional to the 

 whole weight of the respective 

 atmosphere. 



sp. gr. 



Weight of 

 atmosphere. 



Azote - = ^ X .97 = 16.6 

 Oxygen =r^xi.ii = 23.3 

 Aque. va. = -i- X .625 = 0.83 

 Car. acid =i~-x 1.53 = 0.15 



100.88* 



* In order to show the ratios more completely we have assumed the two compound 

 atmospheres differing a little in the total weights. 



MDCCCXXVI. 



sB 



