(*) Lancet, March 16,
1867. (Cf. Camac: Epoch-making
Contributions, etc.,
1909, p. 7.—Ed.)
With the new technique and experimental methods, the
discovery of the specific germs of many of the more
important acute infections followed each other with
bewildering rapidity: typhoid fever, diphtheria,
cholera, tetanus, plague, pneumonia, gonorrhoea and,
most important of all, tuberculosis. It is not
too much to say that the demonstration by Koch of
the “bacillus tuberculosis” (1882) is,
in its far-reaching results, one of the most momentous
discoveries ever made.
Of almost equal value have been the researches upon
the protozoan forms of animal life, as causes of disease.
As early as 1873, spirilla were demonstrated in relapsing
fever. Laveran proved the association of haematozoa
with malaria in 1880. In the same year, Griffith
Evans discovered trypanosomes in a disease of horses
and cattle in India, and the same type of parasite
was found in the sleeping sickness. Amoebae were
demonstrated in one form of dysentery, and in other
tropical diseases protozoa were discovered, so that
we were really prepared for the announcement in 1905,
by Schaudinn, of the discovery of a protozoan parasite
in syphilis. Just fifty years had passed since
Pasteur had sent in his paper on “Lactic Acid
Fermentation” to the Lille Scientific Society—half
a century in which more had been done to determine
the true nature of disease than in all the time that
had passed since Hippocrates. Celsus makes the
oft-quoted remark that to determine the cause of a
disease often leads to the remedy,(*) and it is the
possibility of removing the cause that gives such importance
to the new researches on disease.
(*) “Et causae
quoque estimatio saepe morbum solvit,” Celsus,
Lib. I, Prefatio.—Ed.
One of the greatest contributions of the nineteenth
century to scientific medicine was the discovery of
the internal secretions of organs. The basic
work on the subject was done by Claude Bernard, a
pupil of the great Magendie, whose saying it is well
to remember—“When entering a laboratory
one should leave theories in the cloakroom.”
More than any other man of his generation, Claude
Bernard appreciated the importance of experiment in
practical medicine. For him the experimental
physician was the physician of the future—a
view well borne out by the influence his epoch-making
work has had on the treatment of disease. His
studies on the glycogenic functions of the liver opened
the way for the modern fruitful researches on the
internal secretions of the various glands. About
the same time that Bernard was developing the laboratory
side of the problem, Addison, a physician to Guy’s
Hospital, in 1855, pointed out the relation of a remarkable
group of symptoms to disease of the suprarenal glands,
small bodies situated above the kidneys, the importance
