Endocrinology may be defined as the science
of the ductless glands, and is thus a branch of physiology.
I have not attempted, in this essay, to cover the history
of endocrine anatomy, nor have I searched for early
references to diseases such as diabetes mellitus or
cretinism, diseases which were described long before they
were shown to have any association with the endocrine system.
Only those clinical observations which have contributed to
our knowledge of the physiological role of the ductless
glands, have been mentioned.
The work is not intended to be an exhaustive
review of the subject, but rather an outline, with comments
on a selected number of important pieces of observational
and experimental research. It is based upon original
articles written in English, French and German. Unfortunately,
some early articles are not available in the libraries
to which I have had access, so that occasionally I have
had to resort to quoting another author's account of the
article in question, the source used has been given in each
One standard textbook of physiology states
"the subject of endocrinology belongs entirely to the
twentieth century ". (Lovatt Evans 1947). If this view is
correct, most of the following essay is superfluous, but
I believe that the foundations of endocrinology were laid
during the nineteenth century and that the discovery of
secretin by Bayliss and Starling marked the end of the early
history of the subject. It is true that the term "endocrinology" was not used until the present century and that the concept of the ductless glands forming a specialised system with complex inter-relationships, is of very recent origin. Nevertheless, it was during the eighty years from 1827 to 1907 that knowledge of the function of the endocrine glands was removed from the realms of speculation
and placed upon the surer foundation of experimental evidence.
It is not my purpose to deal with the
speculations of the early anatomists, which were really
working hypotheses, untested by further experiment or
observation I have described the development of our
knowledge on each gland separately, because not until
the twentieth century were the individual glands recognized
as a part of a new system comparable in importance to
the older systems such as the cardio- vascular and
I hope to demonstrate at the end of this
essay that progress in endocrine illustrates to some extent
an increasing application of the scientific method.