126 Prof. W. A. Norton on Molecular Physics. 



that some chemists suppose one kind of atom to exist for mecha- 

 nical science and another kind for chemical science would supply 

 the want. The chemical and mechanical atoms are supposed in 

 reality to be identical ; that is, identically is predicable of two 

 things that are not the same. 



The writer believes that a false step has been unwittingly 

 taken by some chemists in using the word atom without consi- 

 dering that the very foundation upon which they were building 

 their mental conceptions of the laws of combination was simply 

 au hypothesis ; repetition, combined with an illusive appearance 

 of reality and certainty, doubtless contributed to the hold which 

 physical atoms have upon some master minds. Dalton unques- 

 tionably required the notion of physical atoms to define multiple 

 proportions to himself; but at the present day they are a hin- 

 drance, and must be classified with the crystalline spheres of 

 Ptolemy, the electric fluid of the early electricians, and the 

 phlogiston of Stahl. 



74 Brecknock Road, London, N ., 

 December 1869. 



XVII. Fundamental Principles of Molecular Physics. 

 By Professor W. A. Norton. 



[Concluded from vol. xxxviii. p. 214.] 



SINCE the publication of the continuation of my reply to 

 Professor Bayma in the September Number of the Philo- 

 sophical Magazine, my attention has been diverted to other more 

 urgent matters, which have left me little time or inclination to 

 continue the discussion. This I have little occasion to regret, 

 as, upon a full consideration of the case, I have come to the con- 

 clusion that the proper point has been reached for bringing the 

 controversy between Professor Bayma and myself to a close. 

 His objections to my theoretical views have been answered as 

 fully as the case seems to demand, and he has replied at length 

 to my criticisms of his own views. We now stand upon the 

 same ground. Whatever temptation there may be to expose the 

 futility of many of the arguments urged in support of his posi- 

 tions, and call attention to the misconceptions into which he has 

 fallen, I am willing to rest the case here in the hands of the in- 

 telligent and candid reader — only entering a disclaimer against 

 the position taken by my learned and agile opponent, at the close 

 of his reply, that we differ only on " a few points of secondary 

 importance/' and agree, in the main, in our fundamental views. 

 The reader who has had the patience to follow us in this pro- 

 tracted discussion, will not fail to perceive wherein we differ and 



