176 



ON THE EXTERNAL SENSES 



power. And hence we may reasonably conjecture that in some of the 

 lowest ranks of animals, the sensibihty may not exceed, even in their most 

 lifely organs, the acuteness of the human cellular membrane, cuticle, or 

 gums. 



This, however, does not rest upon conjecture, or even upon loose in- 

 definite reasoning. We find in our own system that those parts which 

 are most independent of all the other parts, and can reproduce themselves 

 most readily, are possessed of the smallest portion of sensation ; such are 

 all the appendages of trie true skin, the cuticle, horn, hair, beard, and 

 nails ; some of which are so totally independent of the rest, that they will 

 not only continue to live, but even to grow, for a long time after the death 

 of every other part of the body. 



Now it is this very property by which every kind of animal below the 

 rank of man is in a greater or less degree distinguished from man him- 

 self. All of them are compounded of organs which in a greater c r less 

 degree approach towards that independence of the general system which, 

 in man, the insensible or less sensible parts alone possess: and hence 

 all of them are capable of reproducing parts that have been destroyed by 

 accident or disease, with vastly more facility and perfection than mankind 

 can do. 



1 have once or twice had occasion to apply this remark to the Idbster, 

 which has a power not only of reproducing its claws spontaneously, when 

 deprived of them by accident or disease, but of throwing them off spon- 

 taneously, whenever laid hold of by them, in order to extricate itself from 

 the imprisoning grasp. The tipula pectimformis^ or insect vulgarly called 

 father-long-legs, and several of the spider family, are possessed of a simi- 

 lar power, and exercise it in a similar manner. These limbs are renew- 

 ed by the formative effect of the living principle in a short period of time : 

 but it would be absurd to imagine that in thus voluntarily parting with 

 them the animal puts himself to any very intolerable degree ofpain ; for, 

 in such case, he would not exert himself to throw them off. The gadfly, 

 when it has once fastened on the hand, may be cut to pieces apparently 

 without much disturbance of its gratification ; and the polype appears to 

 be m as perfect health and contentment when turned inside out as when 

 in its natural state. This animal may be divided into halves, and each 

 half, by its own formative and instinctive effort, will produce the half that 

 is deficient^ and in this manner an individual of the tribe may be multiplied 

 into countless numbers. 



In many animals of the three classes of amphibials, insects, and worms, 

 the most dreadful wounds that can be inflicted, unless actually mortal, seem 

 hardly to accelerate death : and hence we have a decisive proof that the 

 pain endured by such animals must Be very considerably and almost in- 

 finitely less than would be suffered by animals of a more perfect kind, and 

 especially by man ; since in these the pain itself, and the sympathetic fever 

 which follows as its necessary result, would be sufficient to kill them in- 

 dependently of any other cause. 



The life of man is in jeopardy upon the fracture or amputation of a 

 limb ; and even at times when his body has been spattered over with a 

 charge of small shot, or only of gunpowder. But M. Riband, with a 

 spirit of experimenting that I will not justify, had stuck different beetles 

 through with pins, and cut and lacerated others in the severest manner, all 

 of which lived through their usual term of life as though no injury had 

 been committed on them. Vaillant wishing to preserve a locust of the 



