4>l4t Di\ Scherev's Abstract of 



traces of the presence of nerves and blood-vessels, yet these 

 could not be supposed to modify their composition in any 

 important degree, as their quantity is excessively minute, and 

 their composition not very different from that of the tissue 

 under examination. 



Tissues imhich yield Gelatine. 



The substances selected as yielding pure gelatine, were isin- 

 glass and the tendons of the feet of young calves. They were 

 both perfectly soluble in^boiling water. The isinglass,when freed 

 from all traces of fat by boiling in aether, and dried at 212°, 

 gave by incineration 0*5 per cent, of ashes. The calves' ten- 

 dons macerated for some time with a solution of nitre to re- 

 move any investing membrane, and then washed perfectly out 

 with pure water, and boiled with alcohol and ajther, gave on 

 incineration 1*6 per cent, of ashes. 



Each material was analysed several times, but the following 

 results need only be given, the others wei'e almost coincident: — 



The sclerotic coat of the eye is composed as the gelatinous 

 tissues, although in its insolubility in boiling water it resem- 

 bles those tissues which yield chondrin. It gave — 



Carbon 50-995"^ 



Hydrogen 7-075 I 



Nitrogen .... 18-723 f 



Oxygen 23-207J 



If we take double the carbon which exists in the formula 



already given for protein as a standard, and calculate from it 



a formula to express the composition of gelatine as given 



above, we obtain Cgg Hg, Njg O.^^ , and subtracting from it two 



equivalents of protein, there remain 3.N Hg with H O and 



7 O, for 



Cgs -"sQ -^15 Oggl _ u MO 

 — C H N O r~ "lo ^^3 ^8* 

 ^x -"ya ■'■^12 ^wj 



Tissues 'which yield Chondrin. 



Chondrin was shown by its discoverer Miiller to exist in 

 the permanent cartilages, in the bones before ossification, in 

 the cornea of the eye, and also in some morbid enlargements 

 of the bones. 



For analysis, Dr. Scherer selected the cartilages of the ribs 



