180 THE DISEASES AND DISOEDERS OF THE OX. 



of matter of a primeval past. The life-work of Charles Darwin, 

 coupled with that of other writers and investigators, such as 

 Herbert Spencer, added the link of vital phenomena to the chain 

 of thought, which was previously incomplete. Now one more link 

 has been hinted at, it is for the observers of this age to rivet it ; 

 and we must not forget that the difficulties which will be expe- 

 rienced by those who try to effect this will proceed rather from 

 a superabundance than from any deficiency of the facts to be 

 gathered together into one unique whole. Those who attempt 

 to trace the idea of evolutiob throughout the mazes of Pathology 

 will have before them a gigantic task, but yet one which most 

 urgently requires to be fulfilled. 



There are so many diflferent points of view from which the 

 subject can be regarded that one may be apt, while insisting 

 upon one or other aspect, to lose sight of the rest. The great 

 thing is that in our investigations we should never put out of 

 mind the essentials of our pursuit, that we should never be con- 

 tent with having traced our subject backwards, until we have 

 actually grasped the very root of the matter, so far as our human 

 intelligence can enable us to do so. In this our humble attempt 

 which follows we shall do our best to set forth clearly a few of 

 the points which have struck us, and we only advance it as a 

 primary sketch which we hope to be able to fill up more in 

 detail at some future time. 



Now, after this brief introduction, we may begin by repeating 

 that the theory of evolution is nothing other than a perfection, 

 or rather, perhaps, an amplification, of the ordinary human 

 methods of reasoning, and, consequently, it will, of course, be 

 applicable to all groups of facts when they are thoroughly under- 

 stood. Granted that there must be in all things an unknown 

 and unknowable factor, which we cannot discuss even cursorily 

 in this connection, since it would draw us away much too far 

 from our subject to do so, we must never rest content with any 

 explanation of a thing or things until we have cleared the ground 

 of every other ascertainable factor ; and the degree to which we 

 succeed in doing this will be a measure of the thoroughness of 

 our investigations. To those who would object to the theory of 

 evolution, that it is not complete, because it does not give a 

 thoroughly intelligible explanation of the actual basis and reality 

 of things, it is to be replied that it achieves the next best object 



