BLOOD. 1 1 7 



of potassium, acetate of lead, aud tartrate of antimony and 

 potash.' 



Magendie's2 observations differ considerably from the above. 

 He arranges in a tabular form^ the following salts Avhich tend 

 to impede the coagulation of the blood : the alkaline car- 

 bonates, nitrate of potash, and nitrate of lime. All observers 

 agree that the free alkalies completely prevent the coagulation. 



The observations of Schultz, INIagendie, and Hamburger 

 show that dilute mineral and vegetable acids prevent the 

 coagulation of the blood, which however thickens, and assumes 

 a syrupy or oily appearance. These statements have been 

 confirmed by myself. 



The following non-mineral reagents have been observed by 

 Magendie to prevent or impede the coagulation of the fibrin : 

 nitrate of strychnine, nitrate of morphine, and nicotine. This 

 statement, as far as regards the nitrate of strychnine, has been 

 denied by Hamburger. 3 



Hunter observed that the coagulation was retarded by the 

 addition of a solution of opium, a statement however which is 

 not confirmed by Hambui'ger. The latter observer notices 

 the effect which is produced by the addition of bile, in pre- 

 venting the coagulation. 



Acceleration of the coagulation. 



The coagulation of the fibrin is accelerated, or at any rate 

 not impeded, by a temperature higher than that of the living 

 blood. According to Hewson, it takes place most rapidly at 

 from 114° to 120°. Scudamore and Schroder van der Kolk 

 assert that the coagulation is accelerated by electricity and 

 galvanic currents, which however is opposed to the previous 

 observations of Kielmeyer and others. Contact with atmo- 

 spheric air hastens the coagulation. 



According to Hamburger, no influence, either in accele- 



' Schultz remarked that hydrochlorate of ammonia, sulphate of potash, and sul- 

 phate of magnesia, retain the blood in a state of fluidity, aud that even the addition 

 of a large quantity of water does not produce coagulation. After the addition of 

 sulphate of soda, the blood could only be prevented from gelatinising by constant 

 stirring, a step that was not requisite with the other salts. 



^ Lemons sur le Sang. Bruxelles, 1839. 



'Op. cit.p. 249. 3 11). p. 45. 



