THE LAW OF SUBSTANCE. 223 



deformation," great masses of centres of condensation 

 quickly unite in immense proportions, and so obtain a 

 preponderance over the surrounding masses. By that 

 process the primitive substance, which in its original 

 state of quiescence had the same mean consistency 

 throughout, divides or differentiates into two kinds. 

 The centres of disturbance, which positively exceed 

 the mean consistency in virtue of the pyknosis or 

 condensation, form the ponderable matter of bodies ; 

 the finer, intermediate substance, which occupies the 

 space between them, and negatively falls below the 

 mean consistency, forms the ether, or imponderable 

 matter. As a consequence of this division into mass 

 and ether there ensues a ceaseless struggle between 

 the two antagonistic elements, and this struggle is the 

 source of all physical processes. The positive pon- 

 derable matter, the element with the feeling of like or 

 desire, is continually striving to complete the process 

 of condensation, and thus collecting an enormous 

 amount of potential energy ; the negative, imponder- 

 able matter, on the other hand, offers a perpetual and 

 equal resistance to the further increase of its strain 

 and of the feeling of dislike connected therewith, 

 and thus gathers the utmost amount of actual 

 energy. 



We cannot go any further here into the details of 

 the brilliant theory of J. C. Vogt. The interested 

 reader cannot do better than have recourse to the 

 second volume of the above work for a clear popular 

 exposition of the difficult problem. I am myself too 

 little informed in physics and mathematics to enter 

 into a critical discussion of its lights and shades ; 

 still, I think that this pyknotic theory of substance 

 will prove more acceptable to every biologist who is 



