ON THE NATURE OF FERMENTATION 
The Introductory Address delivered-in King’s College, London, at the Opening of the Session 
October'1, 1877. 
[Quarterly Journal of Microscopical Science, April 1878.] 
GENTLEMEN.—In making my first appearance as a teacher in King’s College, 
I cannot refrain from expressing my deep sense of the honour conferred upon 
me by the invitation to occupy the chair which I now hold; and, at the same 
time, my earnest hope that the confidence thus reposed in me may not prove 
to have been misplaced. | 
In considering how I could best discharge my duty as the person selected 
to deliver the Introductory Address of the Medical Session, I have felt that 
two courses were open to me: either to spend the short but important time 
at my disposal in an endeavour to convey to the student some sense of the 
exalted privileges, and correspondingly high responsibilities, of the beneficent 
calling to which he proposes to devote himself, or to treat on some special subject, 
in the hope that I might say something which should have interest, and, if 
possible, even instruction, not only for the student, but also for the eminent 
men whom I have the honour to see around me. The latter is the course which 
I have decided to follow, and the subject which I have selected is a short account 
of an inquiry in which I have been engaged in the interval between the cessation 
of my official duties in Edinburgh and their commencement here. The object 
of that investigation was to obtain, if possible, some more precise and definite 
knowledge of the essential nature of a class of phenomena which interest alike 
the physician, the surgeon, and the accoucheur. I allude to the changes in 
organic substances which are designated by the general term fermentation. 
In medicine, the large class of diseases termed zymotic derive their name 
from the hypothesis that their essential nature is fermentative. In obstetrics, 
puerperal fever, the most frequent cause of disaster after childbirth, is now 
regarded by many of the highest authorities as likewise due to fermentative 
disorder ; and, in surgery, among the various causes which may disturb a wound, 
we know that by far the most frequent in operation, and the most pernicious 
in its effects, both upon the wounded part and upon the constitution, is putre- 
factive fermentation. If this be so, it is clear that to understand the nature 
of fermentation must be a matter of the very highest importance, with a view 
to curing or preventing the various evils to which I have alluded. 
What, then, do we mean by fermentation? I shall best approach the 
answer to this question by giving an example. Rather more than a week ago, 
