sease? You are a learned Judge, and yet you
know comparatively little of the subject which is of most vital
interest to mankind. I mean no offence, of course. I am as ignorant of
the Law, as you are of Medicine. Let me open a window that you may
peep in upon the scientific students busy with their investigations.
The 'Germ Theory,' briefly stated, is this. There are all around us
millions of micro-organisms, parasites which thrive and grow by
feeding upon the animal world. In proportion as these parasities
infest, and thrive upon a given individual, so will that individual
become diseased, and it has been shown that in many cases a special
germ will cause a special disease. I could deliver you a lecture,
hours long, upon the classification, morphology, and pathogenic action
of bacteria, but I wish at present to lead your mind into a different
channel. Undoubtedly the most important question in biology is the
immunity from disease-generating germs, which is possessed by various
animals."

"Do you mean that some animals can resist the attacks of bacteria?"
asked the Judge. Anxious as he was to arrive at the point where his
daughter's name would be again introduced, his natural love of
knowledge caused his interest to be aroused as the Doctor proceeded.

"I do," continued Dr. Medjora. "It has long been known that certain
infectious diseases, such as typhoid fever, are peculiar to man, while
the lower animals do not suffer from them; and that, on the other
hand, man has a natural immunity from other diseases which are common
among the lower animals. Again, some species will resist diseases
which become epidemic among others. In addition to an immunity
peculiar to a whole race, or species, we have individual differences
in susceptibility or resistance. This may be natural, or it may be
acquired. For example, the very young are usually more susceptible
than adults. But a difference will also be found among adults of a
race. The negro is less susceptible to yellow fever than the white
man, while, contrarily, small-pox seems to be peculiarly fatal among
the dark-skinned races."

"Have the scientists been able to account for these phenomena?"

"They theorize, and many of them are making admirable guesses. They
account for race tolerance by the Darwinian theory, of the survival of
the fittest. Imagine a susceptible population decimated by a scourge,
and the survivors are plainly those who have evidenced a higher power
of res