Use hi Legal Medicine 41 



Deutsch (9, viiT. 1900, and later) has suggested the use of artificial 

 haemolysins in legal medicine, in the identification of bloods, both 

 fresh and dried. He found that a powerful haemolytic serum dissolved 

 powdered blood completely, the latter being suspended in 9^/00 salt 

 solution. Dried blood to which saline is added brings the haemoglobin 

 of the injured corpuscles into solution, the uninjured corpuscles do not 

 however dissolve even after 24 hours at 37° C. If the dried blood 

 is extracted in normal rabbit serum more haemoglobin goes into 

 solution than with saline, when the proportion added is 1 : 2, whereas the 

 normal serum acts like saline when added in the })roportion of 1:4. 

 When two samples of the same dry blood are brought into suspension 

 in normal and artificially haemolytic serum respectively, a little phenol 

 or toluol being added, the antiserum brings about complete haemolysis 

 after 24 hours, besides leading to the formation of a precipitum, due to 

 the action of precipitins formed in the blood-treated animal in conse- 

 quence of the serum which was injected together with the corpuscles. 

 When washed corpuscles alone are injected precipitins are not formed. 

 In view of the specificity of the reactions observed with human blood 

 corpuscles, he considers that the method can be put to use in a practical 

 way. There can, however, be no question but that the precipitins offer 

 many advantages over the haemolysins for such purposes. 



In the experiments of Bordet (x. 1898, p. 692), it was found that 

 the serum of a guinea-pig treated with rabbit corpuscles exerted 

 no effect on the corpuscles of the normal guinea-pig, nor upon those 

 of the pigeon. Both normal and treated guinea-pig sera act strongly 

 on the corpuscles of the rat and mouse, the normal serum is however 

 less haemolytic. If 2 c.c. of defibrinated rabbit blood is injected 

 intraperitoneally into the blood-immunified guinea-pig, the rabbit 

 corpuscles are destroyed in 10 minutes. This does not happen 

 in the peritoneum of a normal guinea-pig unless inactivated specific 

 serum (heated to 55" C.) is injected together with the corpuscles. The 

 serum of the treated guinea-pig, injected intravenously into rabbits 

 kills them when 2 c.c. are given. This is in substantial agreement with 

 what has been observed with regard to the specific bacteriolysins, for 

 instance with regard to the cholera germ. Bordet considers the 

 haemolysin (alexine) in the treated guinea-pig serum to be probably 

 identical with the sj)ecific bactericidal substance of Pfeiffer. 



The study of the relationships amongst animals by means of artificial 

 haemolysins has scarcely been begun, as we see, if we except the work 

 of Ehrlich and Morgenroth abcn'e cited, which gives corresponding 



