RELATION TO INFECTIOUS DISEASES. 89 



diseases In-iii-; due to chemical poisons. In investigating 

 tin's theory, three possibilities suggest, themselves: 



(a) The microorganisms themselves may ta poisonous, 

 or the poison may IK- ;in integral part of thorn. NEELSEN, 

 at one time an advocate of this theory, thus accounted for 

 the appearance and increase in violence of the symptoms as 

 the germ-. increase in numlxT. In order for the conditions 

 of this theory to l>e fulfilled the microorganisms must be 

 present in the blood before any of the symptoms appear. 

 But in anthrax the most thoroughly studied of all the in- 

 flrtions diseases, and the one to which all these theories 

 have Ixrn applied, the bacilli first appear in the blood, as a 

 rule, only a few hours before death, and long after the 

 appearance of the first symptoms; while in many other 

 diseases the germs are never found in the blood. More- 

 over, as HOFFA has shown, if this theory l>e true, the in- 

 jeetion of a large quantity of anthrax bacilli directly into 

 the blood should be followed immediately by symptoms of 

 tli' disease, and death should l>e speedy. But he found, on 

 making experiments of this kind, that the symptoms did 

 not appear until from twenty-four to seventy-two hours. 

 NENCKI found by analysis that the substance of the an- 

 thrax bacilli resembles Vegetable easein in some respects, 

 and animal mncin in others. This "anthrax protein " is 

 freely soluble in alkalies, is insoluble in water, acetic acid, 

 and the dilute mineral acids. It contains no sulphur and 

 was believed by NENCKI to be inert; but the recent re- 

 searches of BUCHNER has shown that this belief is not well 

 founded. It has IxH'ii stated by a numlxT of investigators 

 that suppuration might lx; induced by the injection of cer- 

 tain sterilized cultures, but the dictum of WEIGERT, "no 

 suppuration without bacteria," has been generally accepted ; 

 and statements to the contrary, although some of them have 

 Ix-en made by men of excellent reputation, have until recently 

 received but little credence. However, BUCHNER has shown 

 conclusively that the albuminate of the bacterial cell in as 

 many as sevenh-en different species jxxssessos well-marked 

 pyogenetic properties, and that the pus formed is free from 

 germs. BUCHNER separated the microorganisms from the 



