THE ETHER. 139 



must be a great and active agent in the work of 

 the universe, as well as an active reporter of 

 what is done by other agents. It must possess a 

 number of complex and refined contrivances and 

 adjustments which we cannot analyze, bearing 

 upon plants and chemical compounds, and the 

 imponderable agents ; as well as those laws which 

 we conceive that we have analyzed, by which it 

 is the vehicle of illumination and vision. 



We have had occasion to point out how com- 

 plex is the machinery of the atmosphere, and 

 how varied its objects; since, besides being the 

 means of communication as the medium of sound, 

 it has known laws, which connect it with heat 

 and moisture ; and other laws, in virtue of which 

 it is decomposed by vegetables. It appears, in 

 like manner, that the ether is not only the 

 vehicle of light, but has also laws, at present un- 

 known, which connect it with heat, electricity, 

 and other agencies; and other laws through 

 which it is necessary to vegetables, enabling 

 them to decompose air. All analogy leads us to 

 suppose that if we knew as much of the consti- 

 tution of the luminiferous ether as we know of 

 the constitution of the atmosphere, we should 

 find it a machine as complex and artificial, as 

 skilfully and admirably constructed. 



We know at present very little indeed of the 

 construction of this machine. Its existence is, 

 perhaps, satisfactorily made out ; in order that we 



