X rUEFACE TO ENGLISH EDITION. 



a devoted and accomplished savant as Pasteur, possessed a 

 scientific interest much wider than their mere relation to the 

 art of brewing would imply. As the work of a skilful chemist 

 and a laborious and accurate observer, such a protracted and 

 careful study of the lowest and simplest forms of life, must 

 necessarily be of first imi^ortance to the biologist — to the 

 beginner as an admirable introduction to the study of practical 

 phj'siology in general, as well as to the more advanced student, 

 from the suggestive light which it throws on the nature of 

 analogous phenomena in more complex organisms. 



I determined accordingly to publuh the work if I could 

 secure the consent of its distinguished author, but at the same 

 time I felt that the publication of M. Pasteur's "Studies" in 

 the form in which Mr. Waite had, at my request, translated it, 

 and illustrated only with inferior copies of the original plates, 

 would not be either advisable or just ; but that I was bound rather 

 to put the book before the English public in as satisfactory and 

 complete a form as lay within my power. Under these cii'cum- 

 stances I was induced to seek the aid of Mr. D. Constable 

 Robb, B.A., of The Oxford Universit}' Museum, who, in taking- 

 Mr. Waite's version as a basis, has so elaborated, annotated, and 

 recast it, that I feel bound to say that much of the value of 

 " Studies on Fermentation," as it now appears, is due to the 

 cure that Mr. Robb has bestowed upon the revision that he so 

 kindly undertook ; a revision the result of which has created a 

 feeling of confidence in the success of the translation as it now 

 .stands, which I could not have had in any mere literal version. 



To the practical worker the original illustrations alone, which 

 appear in this version, cannot but be of immense value in the 

 microscopical study of the changes in the liquids with which 

 he deals; whilst the many notes and additions, which are a 



