BOOK OF NATURE LAID OPEN. 165 



It is seldom, indeed, sufficiently dense at the height 

 of two miles to be able to bear up the clouds ; so that, 

 to whatever perfection our modern aeronauts may 

 bring the art of balloon-navigation, there is not the 

 smallest probability of their being able to escape from 

 the earth to another planet. The atmosphere has its 

 limits as well as the ocean; and not only are those 

 massy bodies that are made to move in the lower- 

 parts of this great outwork of our globe confined by 

 laws, firm as chains of adamant, but the thinnest va- 

 pour, the minutest atom, the most subtile effluvia that 

 ascends the higher regions, and gain, as it were, the 

 outskirts of creation, are checked in their career by 

 the powerful mandate or the Creator, and forced to 

 return and execute his orders. 



Happy, indeed, for the world, is this ordination; 

 for, if the philosophic axiom be true that things must 

 continue as at the beginning, with respect to the quan- 

 tity of matter contained in the universe, and that, if it 

 were possible that a single atom could be lost, the 

 harmony of creation would be destroyed, what dire- 

 ful consequences must ensue, were the daring spirits 

 of adventurous men not confined by unalterable laws, 

 and the imperceptible atoms which float in the at- 

 mosphere not laid under restraint by that command 

 which says to the troubled waves of the ocean, " Hi- 

 therto shalt thou come, and no farther." 



The Uses of the Atmosphere. 



We have already mentioned several of the uses 

 of this invaluable and all-pervading fluid^ in point 



