, 1865-12-15

not, In smallpox we have a disease charac-
terised by pustules over the body. Each pus-
tule contains a secretion Astounding with pus
cells, and the matter with which they are
formed. 1t is the introduction of this purulent
matter into the blood that sets up the dreadful
malady of smallpox. Tn the same way we
find the vesicle Of COW pox charged with white
cells, and the ~''germinal matter of DR.. Beale.
The germinal matter here, however, does not
possess the vitality and energy of that of the
smallpox possible. 1t is seldom conveyed
through the air; like some other animal poi
sons with which we are acquainted, it requires
contact but, in being introduced into the
blood of another person, it produces the same
disease always the same disease, never an
other. We may learn much of the nature Of
these poison-cells by those we know so well.
These cells, or germinal elements, retain their
vitality long after they have been removed
from the body, if you exclude them from the
air. The vaccine lymph has been conveyed
between pieces of glass, or dried on tips of
bone "a threads of line or cotton, all over the
globe, and has been found capable of engender-
ing the disease coW-pox. This shows US how
all these poisons may be covered over in linen
cotton, and W0lIen fabrics, now they can be
conveyed in letters and newspapers, how they
may adhere to inanimate substances of all
kinds, and only need the awaking influence of q
tlUJlo moisture 10 summon IlPm 10 awake anu
live anew, No one, that / am aware, has yet
isolated the poison of scarlet fever, of measles,
of typhus, of cholera, and of the other diseases
of the group of contagious diseases but, rea-
soning from analogy, and there could hardly be
a better instance of the process, we are driven
to the conclusion that these diseases depend on
a cause similar to that Of smallpox, and that
the real form of the poison is the charged
white cell of the blood. 1t is, however, interest
ing to notice some varieties in the habits of
these poisons. Thus, we are not aware that
the poiSons of smallpox measles. scarlet fever,
or typhus, are conveyed by any means but
through air, whilst there is every reason to
believe that the poisons of typhoid fever and
cholera are conveyed by the agency of water.
There is an interesting relation between this
fact and the seat of the disease, for, whilst one
set of diseases manifests itself by eruptiOns
upon the skin, the other set is characterised by
arrangements of the mucous membrane of the
intestines. A question of high interest arises
here, and it is one that has not at present been
settled, and that is, as to whether the poison
matter Of these diseases is capable of multiply
inc itself by cell-diviSions, or the ordinary forms
of the growth of fuvial matter out of, the body.
1t does hob seem impossible that this should
be the case, although at present we have no
demonstration of the fact. We know that such
multiplication takes place among the lower
forms of plants, as the yeast, or fermentfungus,
saccharonycus c~eccoisaa, and that it also occurs
amongst the vibiconds and monadine in the
animal kingdom, Another interesting question
connected with these poisons is the possibility
of Transformation or development. In the ami
NAL kingdom we have this phenomenon taking
place, that an animal passing from its egg state
to its adult stare is capable at each stage of
multiplying itself, so that a number of creatures
are produced at each stage of its growth, ca
pable of attaining, under proper external circum-
stances, the adult stage. Now it may be that
amongst these cell poisons there are stages of
development at each of which the cell is capa-
BILE of propagating its own form and no other,
till it meets with the proper external circum-
stances for a further change or development.
Professor Huxley relates that on board the
Rattlesnake, after they had been six weeks at
sea the cook got an attack of erysipelas. This
spread through the ship and ceased. After
this one of the sailors had the n1umps, and this
also spread through the ship. There are other
interesting facts bearing OF this point, but I
throw out these hints here as subjects full of
practical Importance to the san;tarian. Let me
now say a few words with regard to the means
of conveyance of p%oisons. The most obvious
of these means are the atmosphere and water.
TrL,o 50 - oa~rrv nan roscoo1a ~o.t H.. 1880