Animals and Man Compared, 193 



conditions of life, in each species. There is, also, 

 likeness of substance. If we take a human bone 

 and one from a dog, and analyze them, we find them, 

 throughout of the same chemical composition. 

 The bones grow, and the tissues are combined, in es- 

 sentially the same manner in both. The differences 

 are merely specific, but the generic character of 

 bone is constant. If we compare the muscles of 

 both, the' same is true. Not only are the muscle of 

 a dog and that of a man alike in their general 

 structure, action and use, but they are composed of 

 the same materials, and they grow in the same man- 

 ner. The nervous systems of both have essential- 

 ly the same composition, as they have the same 

 structure and the same use. So, throughout, our 

 comparison will hold, until we satisfy ourselves 

 that, in any one of the higher vertebrate animals, 

 we find the same kind of materials organized in the 

 same manner, and for the same uses, as in our own 

 bodies. Growth, decay, life and death are essen- 

 tially the same, in all the higher animals, as in man. 



Now let us advance a step, and compare the 

 senses and sensations of both. We have no sense 

 which we do not find in some animal ; and the senses 

 of animals, so far as we can judge, are affected 

 in the same way as ours are, by the same objects. 

 They may have some of the senses more acute than 

 ours are, but they differ from ours, only in degree ; 

 as the senses of men differ in strength and delicacy. 

 So far as we know, no animal has a sense that dif- 

 fers from ours, in kind. 



If we examine the phenomena of the senses in 



