MICRO-ORGANISMS AS EXCITING AGENTS OF DISEASE. 97 



Thus from time to time authors have denied that 

 micro-organisms act as exciting agents of the infective 

 diseases of wounds, their views being based more espe- 

 cially on the statements made by several observers, 

 that after mechanical removal of the organisms from 

 infective fluids the filtrate, which is devoid of organisms, 

 exerts pathogenic action. More accurate experiments 

 have however shown that this action depended solely on 

 an intoxication, on a poison in solution, and that there- 

 fore it could not be at all compared with an infective 

 process (Panum, Hiller, Koch, and others). The Billroth's ob- 

 results of Billroth's investigations attracted special at- 

 tention for a considerable time ; he repeatedly found theory, 

 micro-organisms in subcutaneous suppurations, where 

 there was no external wound ; he likewise found them 

 in living organs; and he concluded, therefore, that 

 living germs were always present in the body, but that 

 they were not able to develop in the healthy body, and 

 could not utilise the tissues of the living body as 

 nutritive material. It was not till a " phlogogenous 

 ferment" (Phlogistisches zymoid) had been formed as 

 the result of decomposition, which ferment could of 

 itself cause inflammation, that the conditions were 

 suitable for the development and multiplication of the 

 micro-organisms ; and under favourable conditions these 

 organisms can become carriers, and lead to the multi- 

 plication of this ferment. According to Billroth the 

 micro-organisms originate from a single plant, the 

 Coccobacteria septica, which is characterised by the 

 multiplicity of its vegetative forms, and according to 

 the external conditions appears now in one, now in 

 another morphological form. 



It is easy at the present time to refute Billroth's 

 objections. In the first place, we know from numerous 

 experiments that bacterial germs are not present in the 

 normal living organism in recognisable numbers, and 

 that the numerous organisms in the diseased living body 

 can only be referred to entrance from without to an 

 infection. An objection might, however, be made that the 

 facts made out, as to the absence of pre-existing germs 



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