172 W. A. Norton on Molecular Physics, 
nothing more is essentially implied than that a considerable 
number of atoms of the one occupy the interstices between 
the atoms of the other. Prof. Bayma assumes e great 
differences to subsist between his two attractive forms of mat- 
ter. He remarks, “the distinction of such a medium” (a me 
dium for the transmission of light) “‘from any ponderable 
substance, is not an hypothesis but a necessary inference 
again 
evidence of their similarity is much greater than of their dis 
similarity. | 
In speaking of the two ethers as subtle, it was meant that 
a large number of their atoms occupied the interstices betweel 
the atoms of gross matter. It was also of course recogt 
that the velocity of propagation of a wave is much ot 
through either of the ethereal fluids than through a mass 
ordinary matter. The only apparent force in the quesi 
under consideration, is derived from the fact that a vague ge 
jecture is apt to be raised by it that a single ether may a 
equal to all the duty now assigned to both. 
To proceed with our quotations: 
t we have said on the constitution of molecules ve pot 
8 indeed the necessity of granting to each molecule Ted the 
derable matter a repulsive atmosphere, which we have cal eee 
molecular env er i sether, since 8 
Hage ni eae But this envelope is not of ) | 
That is, is not of the same substance as his oni 
ether, which he regards as attractive. But the “ ae Baya | 
which corresponds in its direct operation with Prof Dayna 
envelope” is composed of electric matte 
; tt is true that I conceive the 1 
this electric matter, and the space betwee? 
| 
| 
a 
ae 
se 
the central atom to be pervaded b the, ether a se 
