hrivel or
perish with dry gangrene, not because the spores of the fungus which
produced the spurred rye circulate in the blood of the chicken, nor that
the spawn or mycelium thus traverses the fowl, but the peculiar and
specific influence acts upon the whole animal precisely like the poison
of the poison oak, producing its specific effect on the most remote
parts of the system, and not as mustard confined to the part it touches.
The mustard acts directly, but the "poison Ivy" acts indirectly; so also
the virus of cow-pox poisons the whole system, but usually appears in
but one spot unless the lymphatics of the whole arm are weak, and in
that case crops of umbilicated pustules precisely like the original, may
recur on all parts of the arm for several months. The specific effect of
ergot or the fungus when indirect is manifested by contracting and even
strangulating the tubes or capillaries causing them to pucker up (as a
persimmon acts directly on the mouth), but in this case permanently
though indirectly, so that rye bread sometimes causes dry gangrene in
the human subject; the shins and feet shrivel precisely as those parts
of the limbs of the pear do, moreover a dark fluid exudes (as the
circulation is arrested where a patch occurs) in both cases alike,
consequently if the remedy in both cases is based on the same
principles, and is demonstrated to be equally effectual, the cause and
the disease are similar.

I have seen dry gangrene in the human subject originate apparently from
an old "frost bite;" which means merely chronic debility of the
capillaries of the foot or shin. Thus the extremities of the pear, or
the weakest part, always succumb first, and the most vigorous trees
never manifest it until they are weakened by their first crop of fruit.
All are familiar with the fact that an old frost bite will swell or
succumb to a temperature which will be innocuous to any other part of
the body. The microscope may invariably reveal fungi in the patch of
pear blight precisely as the housewife discovers the mold plant in her
preserves and canned fruit, and even in the eggs of fowls, the mycelium
(or spawn) penetrating the fruit or preserve though it be covered while
boiling hot. If so, the reason why all parts of the tree are not
attacked at the same time, is not because the fungus is not ubiquitous.
We first notice the action of strychnia in the legs, or in paralyzed
limbs exclusively, because they are weaker and become