﻿184 Prof. J. Bayma on the Fundamental 



saying ('Molecular Mechanics/ p. 2) that a work which was 

 intended to lay down the very first foundation of a molecular 

 theory, could not possibly rest on hypothetical ground, and that / 

 had embodied in the work, as principles of molecular mechanics, 

 those propositions only which were evident, or which I thought I 

 had the power of rigorously demonstrating from known laws of 

 nature ; a proposition which seems to have amazed Professor 

 Norton. But even he will allow, I hope, that, in my capacity 

 of Professor of Philosophy, I can aspire to something better than 

 those hypotheses which are the lot of mere experimentalists. 



And now to come to hk Assertion. I would observe in the 

 first place that, if (t no theo of molecular physics can have any 

 other foundation than gener. rinciples to be regarded as hypo- 

 theses," then no physical t..oory can lead to any other than 

 hypothetical conclusions; and as hypothetical conclusions can- 

 not be called " established truths " in any true sense of the 

 words, it follows that neither Professor Norton's theory nor its 

 principles are " established truths." And this would suffice to 

 justify my stricture that his theory rests upon " a great deal of 

 arbitrary assumption." 



But I must add secondly, in justice to molecular science, that 

 Professor Norton's opinion of it is far from being accurate. 

 Molecular science is not without established principles : it is not 

 a pure heap of hypotheses. That material substance is endowed 

 with active power, passivity, and inertia, for causing, receiving, 

 and conserving local motion: that no natural cause can com- 

 municate a finite velocity to a body in an infinitesimal unit of 

 time : that in the impact of bodies no communication of motion 

 can be made by means of a true and immediate contact of matter 

 with matter : that an increase or decrease of intensity in motion 

 is always due to a real production or extinction of velocity : that 

 material substance acts, ceteris paribus, with different intensity 

 on bodies placed at different distances : that material substance 

 is not prevented by intervening bodies from acting on other 

 bodies placed at a greater distance : that the primitive com- 

 ponents of molecules are unextended elements : that these 

 primitive elements obey the Newtonian law of action : and 

 other points of the like nature, with all their corollaries, are not 

 mere hypotheses, but " established truths," about which I think 

 that the readers of the e Elements of Molecular Mechanics 3 can 

 entertain no doubt. And whilst we must admit that we cannot 

 by means of these truths alone attain to a knowledge of all the 

 secrets of molecular science, we do nevertheless affirm that we 

 have in them a solid foundation to build upon. So false is it 

 that molecular science has no established principles, that even 

 Professor Norton's theory, of which some fundamental prin- 



