9 



V'' 



fully understood, there are few or none who deny its frequent occurrence, 

 and the question is not so much whether phagocytosis plays a part in 

 the prevention of disease, as whether it plays the most important part— 

 whether there are not other factors equally or more impoiiant. 



It is but natural that when the ph:igocyto8is observed was insufficient 

 to account for the number of microbes that had undergone destruction, 

 attention should have been turned to the possible bactericidal action of 

 the blood plasma, and of the humours of the body in which this 

 destruction had taken place. And many workers were led to turn their 

 enquiries into this direction, first among whom may be mentioned von 

 Fodor, Emmerich and di Mattel, Nuttall, Buchner, Nisseu, and Lubarsch. 

 In 1887 von Fodor* found a gradual diminution in the number of bacilli 

 to be obtained by making successive plate cultures at short intervals 

 after inoculating sterile rabbits' blood with growths of anthrax. The 

 blood evidently exercised a bactericidal property. In the following year 

 Nuttallt published some much more extensive and satisfactory obser- 

 vations. Taking the blood serum of the frog in the first place, and 

 afterwards employing that of a long series of animals, including man, 

 he showed that by carefully observing the micro-organisms immersed in 

 the fluids upon the warm stage of the microscope it was possible to 

 follow the gradual degeneration and death of the micro-organisms in the 

 absence of any cellular action. He found that a temperature 

 of 55' C. destroyed the bacteria-killing power, and was of the opinion 

 that serum and other body fluids owed their bactericidal eff'ect to the 

 presence of some ferment. 



This paper was followed by another from the same laboratory at 

 Breslau, in which Nissen; showed that numerous other pathogenic and 

 non-pathogenic bacteria were destroyed by defibrinated rabbits' blood, as 

 for example, the spirillum of cholera, the typhoid bacillus, Friedlander's 

 pneumonia bacillus, and the coccus aquatilis, while others were little 

 affected and some grew abundantly. Such were, among others, the 

 pyogenic staphylococci and the microbes of fowl cholera and of swine 

 erysipelas. Some of the former were killed so rapidly that Nissen con- 

 cluded that the swiftness of their destruction outside the body was in 

 itself an argument against phagocytosis, and instituted experiments to 

 show that a similar swift destruction occurs within the blood vessels of 

 the organism— but inasmuch as he made no series of cultures from the 

 organs in whose capillaries the injected microbes might have been 

 arrested, his results are, in this respect, of but little value. Emmerich 



■" von FoAov.— Deutsche med. ]f'ochenschrift, 1SS7, p. 745. 



t Nuttall. " Experimente fiber dio biikterienfelndlichen Elnfliisae des thierisclicu Korpcrs." 

 —Zdtsch: f. Hygiene. Vol. IV., 1SS8, p. 35;i. 



{Nissen. "Die baoterienvorniohtendo Eigenschaft des B\\ites."—ZeUscKr.f. H'jgieM, \ol. 

 VI., ISSO, p. 487. 



