LIQUID PARTS OF ANIMALS. 



2. The vitreous humour possesses the same properties as the 

 aqueous. Its specific gravity, as determined by Chenevix, is the 

 same as that of the aqueous humour. Its constituents, accord- 

 ing to the analysis of Berzelius, are 



Water, . . . 98-40 



Albumen, . . . 0-16 



Chlorides and lactates, . . 1-42 



Soda, with animal matter soluble only in water, 0-02 



100-00 



3. The crystalline lens is solid and transparent, it is com- 

 posed of a congeries of very fine coats. Its specific gravity is 

 1-1000. But it is densest and most solid in the centre, and the 

 specific gravity and consistency gradually diminish as we ap- 

 proach the circumference. Chenevix found the weight of a fresh 

 crystalline lens of an ox to be 30 grains, and its specific gra- 

 vity was 1-0765. On paring away the external portion, and leav- 

 ing only a central nucleus weighing 6 grains, the specific gravity 

 of this nucleus was 1-1940. 



It dissolves almost entirely in water. The solution is partly 

 coagulated by heat and gives a copious precipitate with tannin, 

 both before this coagulation and after it. Berzelius conceives 

 that this property is owing to the presence of a peculiar matter 

 possessing all the characters of the colouring matter of the blood, 

 except the red colour. But what was considered as the colour- 

 ing matter of blood when Berzelius made his experiments, was 

 chiefly albumen, but containing a very little fibrin and hemato- 

 sin. Hence it is probable that this peculiar matter is chiefly al- 

 bumen. The constituents of the lens were found by him to be, 

 Water, . 58- 



Peculiar matter, . . .35-9 



Chlorides, lactates, animal matter soluble in alcohol, 2-4 

 Animal matter soluble only in water, with phosphates, 1 -3 

 Insoluble cellular membrane, . . 2*4 



100-0 



The peculiar matter of the lens when burnt leaves a little ash 

 containing a very small portion of iron. When its solution in 

 water is coagulated by boiling, the liquid in which the coagulum 

 was formed reddens litmus, has the smell of the humours of the 

 muscles, and like them, contains free lactic acid. 



