290 CONTINUOUS VIBRATORY MOVEMENT OF 



separation within the limits of their appropriate agitation. The nature of thig 

 movement must vary with the nature of the bodies, each of them having a par- 

 tiouhir movement wliich constitutes its normal state and impresses on it a special 

 character. We can comprehend, therefore, that when two bodies are placed in 

 contact, there must be a communication, a transference of their oscillatory and 

 rotary movements, with loss on the one side and gain on the other. Let us take 

 an example : suppose the initial molecular movement of copper to be more intense 

 than that of zinc ; if the copper comes into collision with the zinc it will lose, 

 according to the laws of mechanics, a part of its inherent force eipial to that which 

 the zinc acquires. We conclude hence that the copper, considered as the col- 

 liding body, is negative, w'hile the assailed zinc is positive. , 



Would it be rational to suppose that mechanical laws are tiiie when percep- 

 tible masses are in question, and yet control neither atoms nor the particles of 

 subtile matter? If it be true that there is nothing ahsohdely large nor absolutely 

 little in creation, dimensions can never constitute a difference in relation to the 

 forces which produce and the laws which govern phenomena. We consider then 

 the action of light on the object which it renders visible, and that of heat which 

 elevates its temperature, as something of an analogue to the sympathetic vibra- 

 tion of a chord at the moment when the sound of another chord traverses the air. 

 After an analogous manner, all actions at a distance and electro-magnetic induc- 

 ti(jns present themselves as natural consequences of one same mechanical principle, 

 conformably to the general economy of the system of the universe. 



One of the inost important consequences of this study is that sound, light, heat, 

 electricity,* are not real entities, but simply modes of action and movements of 

 matter communicated to our brain through the medium of the nerves. Tlie human 

 organism may therefore be considered as an elastic system, of which the different 

 parts receive the shocks of elastic mediums, and vibrate in unison with a certain 

 numl)er of undulations each of which produces its complete effect independently 

 of others. Here science stops ! The mysterious influence of matter on mind we 

 must be content to regard as a secret which will yet be long hidden from us. 



Be it remarked that in the order of animated beings there are those which 

 might be clustered in myriads on the point of a needle, and which live l)ut a few 

 seconds ; and yet to them their life seems long and complete, and during those 

 few seconds they may have a perception of niillitms of shocks such as those which 

 constitute heat. There may very probably exist other beings which can never 

 have a perception of a complete undulation of the ether, and which scarcely dis- 

 tinguish a feeble portion of one ; in fine, even these elementary portions will 

 always appear too complex to certain other beings which perceive nothing but 

 the individual movements and displacements of atoms. These considerations 

 enable us to appreciate how very limited are our senses, for, as has just been 

 seen, the human race occupies but a few degrees of the indefinite scale of sensi- 

 bility. Herein, perhaps, is one of the jjrincipal motives why man is often diverted 

 from truth, even while seeking it; the instinctive repugnance which he feels to 

 meditate upon simple and common phenomena, and to extend the laws which 

 govern the domain that he is able to explore beyond the limits of his own sensi- 

 bility, has led him to imagine complicated systems and to have recourse to the 

 hypothesis of mysterious principles. 



These reflections lead us to another important consequence, namely, that if the 

 philosophers who have considered our world as an atom in creation are right, 

 under a certain point of view, we ought yet to recognize, witli other philosophers, 

 that each atom is a world. Each atom possesses a proper activity, and is the 

 seat of all the natural forces; these never manifest themselves outside of matter, 



[* The author is not warranted bj the present state of science to include electricity in the 

 same class with sound, light, and heat. In statical electrical repulsion, which inauit'ests 

 itself at a great distance, we have u pheuomeuon entirely unlike any eli'ect exhibited by sound, 

 light, or heat.— J. H.j 



