1835. Saline Solutions on Fibrin. S&f 



that the fibrin would not dissolve in any solution of salt 

 heated to 130° or upwards. This conjecture was fully con- 

 firmed on trial. Fibrin put into solution of salt at any 

 temperature above 130°, did not dissolve, and could not 

 afterwards be dissolved, even at the ordinary temperature. 

 It is, therefore, evident that exposure to heat produces 

 some change on fibrin, which prevents its dissolving in solu- 

 tion of salt, exactly as heat renders ordinary albumen inso- 

 luble in water. This accounts for the failure of my first 

 trials with muriate of ammonia, for I had heated the solu- 

 tion with the view of accelerating the process ; and Berze- 

 lius appears to have operated in the same manner. 



4. The portion of fibrin which dissolves bears a striking 

 analogy to soluble albumen. This led me to suspect that 

 its coagulation might be owing to some serum still adhering 

 to the fibrin ; but the same results were obtained however 

 carefully the fibrin was washed. And, on the other hand, 

 the fibrin, when kept in pure water, underwent no percep- 

 tible change, and the water did not extract from it any albu- 

 minous matter, for it remained perfectly transparent when 

 boiled. The presence of the salt, therefore, is necessary to 

 resolve the fibrin into the albuminous matter. 



5. Some of the solution (1) was mixed with an aqueous 

 solution of corrosive sublimate. No precipitate was pro- 

 duced. I at first supposed that this indicated a decided 

 difference between soluble albumen and the substance which 

 the saline solution extracts from fibrin ; but, on making the 

 trial, I found that 'a solution of white of egg, mixed with 

 common salt, is not precipitated by corrosive sublimate. 

 This fact I now find had been previously noticed. 



6. Some of the same fibrin, prepared from human blood, 

 carefully dried at the ordinary temperature, and which had 

 been kept in the dry state for several weeks, was acted on 

 by the solution of salt almost exactly as the recent moist 

 fibrin. It swelled, became white, then transparent and 

 gelatinous, and in a few hours dissolved, leaving a minute 

 quantity of whitish matter, which did not cohere like the 

 mucus left by the recent fibrin. The solution yielded copi- 

 ous coagula when heated, exactly like the solution of the 

 recent fibrin. 



7. The solution of common salt employed in the above 



