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should not lightly be undertaken or undergone. It is, of course, a 
source of scientific congratulation that so many persons should be 
not only willing, but anxious to be operated on, but they should, I 
think, be explicitly informed by doctors that the treatment is only 
in the experimental stage, that its curative effect is far from certain, 
while its dangers are grave and numerous. With the exception of 
Pasteur’s experiments for hydrophobia, it is the first time that 
experiment on the human subject has been sanctioned by the 
public, and { doubt very much if they knew more of the subject 
whether they would so cheerfully submit to it. Various theories 
have been suggested to explain the method by which poisonous 
germs develop in the system, and there generate chemical poisons. 
There is no doubt a continual struggle is taking place in the 
system between the healthy cells in the blood and tissues of the 
body, and the poisonous germs which we unconsciously breathe in 
with the air and swallow with our food. In a perfectly healthy 
body the foreign germs seem to be actually devoured and digested 
by the white blood corpuscles, and are rendered absolutely 
innocuous. But in caseswhere the system is unhealthy or enfeebled, 
the poisonous microbes become in their turn the attacking party 
and destoy the blood cells, consume their nutriment, and finally 
generate a chemical poison which effects the whole system and 
induces illness. This at least is the theory of Metschnikoff, 
Armand, Ruffer, and others, though I must tell you it is vigorously 
contested by other scientists. This struggle or battle between the 
healthy cells and the intruders has been admirably depicted by M 
Metschnikoff who has not only (microscopically) witnessed this 
conflict, but has made excellent diagrams of the result of his 
observations. In the diagrams now before you, copied from M. 
Metschnikoff, may be seen the intrusive germs beset, devoured, 
and actually digested by the blood cells. while in some may be seen 
a blood cell attacked and destroyed by the microbes. 
The amceboid cells, whose beneficent functions it is to prey upon 
and devour inimical germs, are termed phagocytes (Gk. phagein, to 
eat); they are subdivided into macrophages, large or tissue cells, 
and microphages, small cells. In an interesting article by Dr. 
Alfred Schofield on this subject, he tells us it is believed that the 
process by which a tadpole loses its tale is due to the voracious 
instincts of these phagocytes, and those germs which prey upon all 
dead organic matter, and which commence their work the moment 
that life is extinct. It is a remarkable fact that during life the 
animal body is able to defy those special microbes known as decay- 
producing bacteria or saprophytes. 
Dr. Armand Ruffer has published some highly interesting notes 
of investigations made by him concerning the conflict between the 
