nature's mechanics. 275 



'far as the telescope can survey in the one direction, 

 and the microscope in the other. 



The organisations of animals do not partake of the 

 unseen and, therefore, the mysterious nature of that 

 energy of life by which they are evolved and put in 

 motion. They are, in all their parts, wholly material, 

 -and every motion, and every position of rest, of which 

 they are capable, admits of as certain explanation — 

 an explanation as simple, if we would go the right 

 way to it, as the putting of a common balance in 

 equilibrio, by placing equal weights in both scales. 

 A leech may proceed by suckers, but no animal pro- 

 ceeds thus, unless its principal action in motion is a 

 lengthening and shortening of the body ; and when 

 we say of a swift-footed animal, that it must pause at 

 every step, and either fasten its foot by glue, or by 

 pumping out the air from under it, we afford a very 

 certain proof, not only that we are imperfect in the 

 knowledge of nature's mechanics, but that we do not 

 understand the meaning and application of those 

 common laws of mechanics, which are set down in the 

 books, although we may be able to parrot the enun- 

 ciations. When w^e do not understand by w^hat 

 means, or in what manner, an animal, or a particular 

 organ of an animal, which is new to us, and, philoso- 

 phically speaking, everything which we do not under- 

 stand is new to us, though we should have been in 

 the habit of seeing it daily for the longest life — when 

 we do not thus understand, the most candid, and by 

 far the wisest plan, is to say so, because all mankind 

 like candour in others, and thus we win the applause 

 of the whole world, without any admixture of that 

 envy or jealousy, which is just as apt to follow a 

 false discovery as a true one; and besides, we leave 

 uncloyed, and in full vigour, that appetite by which 

 T 2 



