GELATINE AND CHONDRINE. 309 



nous seeds. It may be extracted from their meal by cold 

 water and kept in solution. In this solution it resembles the 

 others, but is distinguished from them in this, that its solution 

 is not coagulated by heat. When the solution is heated or 

 evaporated a skin forms on its surface, and the addition of an 

 acid causes a coagulum just as in animal milk. 



" The analysis of these three vegetable principles has led to 

 the interesting result that they all three contain sulphur and 

 nitrogen and the other constituents in the same proportion, 

 and, what is still more remarkable, that they are identical in 

 composition with albumen, containing the same elements in 

 the same proportion as that chief constituent of the blood."* 



Gelatine and Chondrine. The proximate azotised principles 

 hitherto spoken of are known as the albuminoid group. Gela- 

 tine and chondrine are obtained from substances existing only 

 in the animal kingdom, known as the gelatigenous group of 

 bodies. Neither gelatine nor chondrine appear to exist under 

 the soluble form in the animal body. In short, the principles 

 termed gelatine and chondrine are in all cases the result of the 

 prolonged action of boiling water on the gelatigenous or chon- 

 drine - producing tissues. Nevertheless, the composition of 

 gelatine is identical with that of the tissue which yields it by 

 boiling. Thus, a given quantity of tendinous matter, when 

 converted into gelatine by boiling it with water, is not altered 

 in weight. Gelatine and chondrine contain a smaller amount 

 of carbon, and a larger quantity of nitrogen, than the principles 

 of the albuminoid group. The proportion of sulphur is con- 

 siderably less. Chondrine contains more oxygen and less 

 nitrogen than gelatine, while the percentage of carbon and 

 hydrogen is the same in both substances. In 100 parts of 

 gelatine there are, according to Mulder, carbon, 50.40 ; hydro- 

 gen, 6.64 ; nitrogen, 18.34 ; oxygen and sulphur, 24.62. 

 * Liebig, 'Familiar Letters on Chemistry,' 1851, p. 349. 



