104 CHONDEINE. 



during four hours, and observe that it dissolves, and 

 that a solution of chondrine is formed, which on cooling 

 gelatinises. 



2. To the hot solution of chondrine add acetic acid, 

 decant the fluid from the precipitated chondrine, and 

 mix it with alcohol and ether. The dry product is 

 pure chondrine. 



3. Compare a solution of ordinary gelatine with the 

 chondrine solution, and observe that the former is not 

 precipitated by acetic acid. 



4. To a pure watery solution of chondrine add some 

 chloride or acetate of sodium, then acetic acid, and 

 observe that the precipitation of chondrine does not take 

 place. 



5. Place a watery or alkaline solution of chondrine in 

 the polaroscope, and observe that it rotates towards the 

 left; the alkaline solution the more so, the more 

 alkali it contains. 



6. Boil with sulphuric acid and treat the acid liquid 

 as described under leucine, and obtain this body. 

 Observe that no glykokM can be obtained. 



7. Boil cartilage or chondrine with concentrated 

 hydrochloric acid until a sample after having been 

 made alkaline reduces Trommer's copper solution. 

 Boil the mixture with litharge, filter; to the filtrate 

 add basic lead acetate and ammonia ; isolate the pre- 

 cipitate, decompose it with hydrothion, evaporate to a 

 small bulk. The syrup obtained is fermentescible 

 glucose. 



8. To a solution of chondrine in hot water add 

 alcohol : the chondrine will be precipitated in flakes. 



