42 STUDIES ON FERMKNTATION. 



we espouse, and by facts alone we should test the truth of 

 doubtful discoveries. We are but on the threshold of the 

 exploration of our subject, and we should strive to discover new 

 facts in connection with it, and should deduce from these, what- 

 ever they may be, only such conclusions as they may strictly 

 warrant. Unfortunately, there is amongst physicians a tendency 

 to generalize by anticipation. Many of them are men of rare 

 natural or acquired talent, endowed with keen powers of intellect, 

 and the art of expressing themselves fluently and persuasively ; 

 but the more eminent they are, the more they are occupied by 

 the duties of their profession, and the less leisure they have for 

 the work of investigation. Urged on by that thirst for know- 

 ledge which belongs to superior minds, and perhaps, in some 

 measure, through associating with the upper classes of society, 

 which are becoming more and more interested in science, they 

 eagerly seize upon easy and plausible theories, readily adapted for 

 statement which is general and vague just in proportion to the 

 unsoundness of the facts on which they are based. When we see 

 beer and wine undergo radical changes, in consequence of the 

 harbour which those liquids afford to microscopic organisms that 

 introduce themselves invisibly and unsought into it, and swarm 

 subsequently therein, how can we help imagining that similar 

 changes may and do take place in the case of man and animals ? 

 Should we, however, be disposed to think that such a thing must 

 hold true, because it seems both probable and possible, we must, 

 before asserting our belief, recall to mind the epigraph of this 

 work : the greatest aberration of the mind is to believe a tJtinrj 

 to be, because we desire it. 



One of the most distinguished members of the Academy of 

 Medicine, M. Davainne, who was the first to give his attention 

 to rigorous experiments on the influence that organic ferments 

 exercise on the production and propagation of infectious 

 diseases, declares that the idea of his researches on splenic 

 fever and malignant pustule was suggested to him by his 

 perusal of our work on butyric fermentation, published in 1861. 

 In 1850 this gentleman and M. Rayer discovered in the blood 



