366 Dr. Rainy on the Action of [Nov. 



suggested by Professor Miiller's valuable paper on the Blood, 

 which appeared in one of your late Numbers. 



I am, Sir, 



Your Obedient Servant, 



Harry Rainy. 

 Glasgow, \^th October, 1835. 



Though it has been generally admitted that fibrin agrees 

 in its chemical properties with coagulated albumen, it has 

 been stated explicitly by Tiedeman and Gmelin, and more 

 recently by Miiller, that fibrin is distinguished by the pro- 

 perty of dissolving readily in a solution of muriate of am- 

 monia. Such authorities would seem to leave no doubt with 

 regard to the fact ; yet, on repeating the experiment fre- 

 quently some months ago, I did not observe any solution ; 

 and I have since noticed that Berzelius had been equally 

 unsuccessful. From these discrepancies it was obvious that 

 there must be some peculiarity either in the state of the 

 fibrin itself, or in the manner of conducting the process, 

 that materially influences the result. 



My attention has recently been recalled to this subject by 

 accidentally observing that some fibrin prepared from 

 human blood, dissolved almost entirely in a solution o^ com- 

 mon salt, into which it had been put for the purpose of 

 preserving it in a moist state. I was led, by this circum- 

 stance, to perform the following experiments : — 



1 . A portion of moist fibrin, recently prepared from human 

 blood, and very carefully washed, was put into a diluted 

 solution of common salt, at the ordinary temperature. It 

 gradually swelled, assumed a gelatinous appearance, and in 

 the course of twenty-four hours, dissolved in the liquid, 

 with the exception of a weak portion of a mucous-like sub- 

 stance, which formed a thin stratum at the bottom of the 

 phial, and which did not dissolve by adding fresh solution. 



2. The solution of fibrin (1 .) was clear, and frothed readily 

 on agitation. When heated, it became opaque, and deposited 

 copious white coagula. This took place at 130° Fahren- 

 heit ; consequently, rather at a lower temperature than that 

 at which ordinary albumen coagulates. The precipitate did 

 not re-dissolve on cooling, and seemed, in every respect, to 

 agree in its properties with coagulated albumen. 



3. It was natural to suspect, from the last experiment, 



