2 RELATION OF THE ANIMAL 



parts of the animal system contain, in the normal 

 state, a certain amount of water. 



Relation of Animal membranes, tendons, muscular fibres, 

 sues to cartilaginous ligaments, the yellow ligaments of 

 the vertebral column, the cornea, transparent and 

 opaque, &c., all contain, in the fresh state, more 

 than half their weight of water, which they lose, 

 more or less completely, in dry air. 



On the presence of this water depend several of 

 their physical properties. The fresh, opaque, milk- 

 white cartilages of the ear become, when dried, 

 translucent, and acquire a reddish yellow colour. 

 Tendons, when fresh, are in a high degree flexible 

 and elastic, and possess a silky lustre, which they 

 lose when dried. By the same loss of water they 

 become, further, hard, horny, and translucent, and 

 when bent, split into whitish bundles of fibres. The 

 sclerotic coat is milk-white when fresh, and becomes 

 transparent by desiccation. 



When these substances, after having lost, by 

 drying, a part of the properties which they possess 

 in the fresh state, are again placed in contact with 

 pure water, they take up, in 24 hours, the whole 

 original amount of water, and recover perfectly 

 those properties which they had lost. The opaque 

 cornea, or sclerotic coat, which had become trans- 

 parent by desiccation, again becomes milk-white, 

 while the transparent cornea, which had been ren- 

 dered opaque by drying, now becomes again trans- 

 parent. The tendons, which, when dried, had become 



