LIQUORS OF THE EYE. 515 



II. The humours of the human eye are composed of the same 

 ingredients as those of the sheep ; though they differ somewhat 

 in their specific gravity. The specific gravity of the aqueous and 

 vitreous humours is 1 -0053, and that of the crystalline lens 1 -07 90 

 as determined by Chenevix. 



III. The humours of the eyes of oxen resemble those of the 

 sheep in their composition. The specific gravity of the aqueous 

 and vitreous humours is 1*0088, and that of the lens 1*0765, as 

 determined by Chenevix. 



From the specific gravities of the aqueous and vitreous hu- 

 mours compared with that of the lens in different animals, Che- 

 nevix has concluded that the difference between the density of 

 the aqueous and vitreous humours and of the lens, is in the in- 

 verse ratio of the diameter of the eye, taken from the cornea to 

 the optic nerve. 



IV. Chenevix examined also the humours of the eyes of birds. 

 He found them composed of the same materials as the eyes of 

 sheep. But in birds the specific gravity of the vitreous humour 

 was greater than that of the crystalline. * 



V. Lassaigne examined the vitreous humour of a blind horse. 

 Its specific gravity was 1*059, while that of the vitreous humour 

 from a healthy eye was only 1*0008. The vitreous humour in 

 the blind horse was very thick, yellowish, red and muddy, from 

 coagulated albumen floating in it. The albumen in solution 

 amounted to about eight per cent. It was yellow, soluble in alco- 

 hol, and resembled the brown colouring matter of bile, and the 

 salts (similar to those in blood) were more abundant than in 

 the healthy vitreous humour, f 



In the year 1821, Dr Rudolph Brandes made a chemical ana- 

 lysis of the crystalline lens of a horse,J and obtained the follow- 

 ing constituents : 



Water, ... 75 



Albumen soluble in cold water, . 7 



Albumen insoluble in cold water and ap- 1 , ^ 



preaching fibrin in its nature / 



Sulphate, muriate, lactate of potash and ^ 



soda, with a substance precipitated by >- 1 

 tincture of nut-galls, ) 



95 



* Journal of the Royal Institution, i. 297. f Jour * Chim. Med. iv. 476. 

 \ Schweigger's Jour, xxxi. 194. 



