Among the laboratories which I mentioned, one of the most important is
that of pathology and morbid anatomy, or the study of diseased tissues
and organs. The first work on pathology written in this country was
by one of our best-known surgeons, the late Samuel D. Gross, and one
of his most important contributions to surgical progress consisted in
his persistent advocacy of the need for the study of pathology as a
basis for all our means of cure. This is evident, if we consider the
illustration I used a moment ago of a steam-engine. Unless he knows
precisely the defects of such a machine, the influence of fresh or
salt water on a boiler, the influence of rust, the effect of oils,
entirely apart from the mere mechanism of the engine, an engineer
might make the most serious mistake, resulting in fatal damage, both to
the machine and probably to life. So, surgical pathology is the study
of the processes of disease, the alterations in the minute structure
of tissues and organs, without which no surgeon can be fitted for
his task, much less can he be called an accomplished surgeon. All of
these laboratories mark the difference between the scientific and the
empirical method. The old student of medicine went from case to case,
heard many a good maxim, and learned many a useful trick; but, after
all, it was only an empirical knowledge which he obtained. It did
not go to the foundation of things, it was not scientific, as is the
collegiate instruction of to-day.
Having now glanced rapidly at the improvement in medical instruction,
let me turn next to a few of the principal discoveries which have made
the surgery of to-day so much superior to the surgery of a hundred
years ago.