24 BACTERIOLOGY. 



now, the stage to which the subject had developed 

 when these observations were recorded did not admit 

 of their meeting with unconditional acceptance. The 

 only strong argument in favor of the- etiological rela- 

 tion of the organisms that had been seen, to the diseases 

 with which they were associated, was the constancy 

 of this association. No efforts had been made to isolate 

 them, and few or none to reproduce the pathological 

 conditions by inoculation. Moreover, not a small num- 

 ber of investigators were skeptical as to the impor- 

 tance of these observations ; many claimed that micro- 

 organisms were normally present in the blood and 

 tissues of the body, aud some even believed that the 

 organisms seen in the diseased conditions were the result 

 rather than the cause of the maladies. It is hardly 

 necessary to do more than say that both of these views 

 were purely speculative, and have never had a single 

 reliable experimental argument in their favor. Billroth 

 and Tiegel, who held to the former opinion, did endeavor 

 to prove their position through experimental means, but 

 the methods employed by them were of such an untrust- 

 worthy nature that the fallacy of deductions drawn from 

 them was very quickly demonstrated by subsequent in- 

 vestigators. Their method for demonstrating the pres- 

 ence of micro-organisms in normal tissue was to remove 

 bits of tissue from the healthy animal body with heated 

 instruments and drop them into hot melted paraffin, 

 holding that all living organisms on the surface of the 

 tissues would be destroyed by the high temperature, and 

 that if decomposition should subsequently occur it would 

 prove that it was the result of the growth of bacteria in 

 the depths of the tissue to which the heat had not pene- 

 trated. Decomposition did usually set in, and they 



