The Sun.
London, England, 1870-09-15 00:00:00

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VHF, UN, LONDON SEPTEIVIB. , :87U

mover, nee less, cioseols bound up with that of
the nafosted organism. Yon atm familiar with whet
happens in vaccination. A minute cut is made in
the skin, and an infinitesimal quantity of vaccine mat ter
is inserted into the wound:* Within a certain time a
vesicle appears in the place of the wound, and the fluid
which distends this vesicle is vaccine matter, in quantity
a hundred or a thousandfold that 'which which was origi-
nally inserted. Now what has taken place in the course of
this operation? Has the vaccine matter by its irritative
property produced a mere blister, the fluid of which has
the same irritative property ? Or does the vaccine matter
contain living particles, which have grown and multiplied
where they have been planted? -The observations of M.
Chauveau, extended and confirmed by Dr. Sanderson
himself, appear to leave no doubt upon this head. Experi-
ments, similar in principle to those of Helmholtz on fer-
mentation and putrefaction, have proved that the active
element in the vaccine lymph is non-diffusable, and con •
sists of minute particles not exceeding 1-20,000 th of an
, inch in diameter, which are made visible in the
, lymph by the microscope. Similar experiments have
proved that two of the most destructive of epizootic
diseases, sheep-pox and glanders, are also depen.-
' dent for their existence and their propagation upon
extremely small living solid particles, to which the title of
micros/dozes is applied, In both cases it is the solid living
particles which are efficient ; the liquid iu which they
float, avid. at the expense of which they live, being /alto-
gether passive. Now arises the question, are these
microzymes the results of Homegenesi.g, or of Xelogenesis ;
are they capable, like the Porulee of yeast, of arising
only by the development of pre-existing germs;
or may they be, like the constituents of a nut-
gall, the results of a 'modification and individualisation
of the tisanes of the body in which they are found, result-
ing from the operation of certain conditions? Are they
parasites in the zoological sense, or are they merely what
Virchow has called heterologous growths ?" A parasite
may be stamped out by destroying its germs, but a
pathological product can only be annihilated by remov-
ing the conditions which give rise to it. It 'ap-
pears to me that this great problem will have to be solved
for each zymotic disease separately, for analogy cuts two
ways. I have dwelt upon the analogy of pathological
modification, ..which is in favour of the xcnogenetic
origin of microzymes ; but I must now speak of
the equally strong analogies in favour of the
origin of such pestiferous particles by the ordinary
process of the !generation of like from like.
It is at present a well-established fact that certain dis-
eases, both of plants and of animals, which have all the
characters of contagious and infectious epidemics, are
caused by minute organisms. The smut of wheat is a
well-known instance of such a disease, and it cannot be
doubted that the grape-disease and the potato-disease fall
under the same categorii. 'Among animal', insects are
; wonderfully liable to the ravages of contagious and infec-
tious diseases caused by microscopic Fungi. It has been
ascertained that when a spores falls upon the body
of a fly, it begins to germinate and sends out a
process which bores its way through the fly's skin ; this,
having reached the interior cavities-of its body, gives off
the minute floating corpuscles which are the earliest stage
of the Empusa. The disease is " contagious," because a
healthy fly coming in contact with a diseased one, from
which the sporebearing filaments protrude, is pretty sure
to carry off a spore or, two. It is " infectious. ' because
the spores become scattered about all sorts of matter in
the neighbourhood of the slain flies. The silkworm has
long been known -to be subject to a very fatal
contagious and infectious disease called the mus-
cardine. Audouin. transmitted it by inoculation.
This disease is entirely due to the development of a fungus
Botrytis Bassaina, in the body of the caterpillar ; and its
contagiousness and infectiousness are accounted for in the
same way as those of the fly-disease. But of late years a
more serious epizootic has appeared among the silkworms;
and I may mention a few facts which will give you some
conception of the gravity of the injury which it has
inflicted on France alone. The 'production of silk has
been for centuries 'an important branch of industry in
Southern France, and'in the year 1853 it had attained
such a magnitude, that the annual produce of the French
sericulture was estimated to amount to a tenth of that of the
whole world, and represented a money value of 117,000,000
of francs, or nearly five millions sterling. What may
be the sum which would represent the money-value of all
the industries connected with the working up of the raw
silk thus produced is more than I can pretend to estimate.
Suffice it to say, that the city of Lyons is built upon
French silk, as much as Manchester was,upon American
cotton before the civil war. The new disease of the silk-
worm-. is, in' every respect, comparable •to the cholera
among mankind. But it differs from the cholera,
and, so far, •is a more formidable disease, hi
being beriditary, and in being, under some cir-
cunistaneee, contagions, as well as infectious. There
can be no reason, then, for doubting that, among
insects, contagious and infectious diseases, of great mali,-
nity, aro-caused by minute organisms which are produced
from pre-existing germs, or by Homogenesis ; and there
is no reason, that I know of, for believing that what
happens in insects may.not take place in the highest
animals. Indeed, there is already strong evidence that
some diseases of an extremely malignant and fatal cha-
racter to which man is subject, ar© as much the work of
minute organisms as is the rebrine, or last silk-worm
disease. It seems to me impossible to dis-
believe that the lamentable mortality which so
frequently dogs the* footsteps of the most skilful
operator, and those deadly consequences of wounds and
injuries which seem to haunt the very walls of great
hospitals, and are, even now, destroying more men than
die or bullet or bayonet, are due to the importation of
minute organisms into wounds, and their increase and
'multiplication: and that the surgeon who saves most lives,
will be he who best works out the practical consequences
of the hypothesis of Redi
At the conclusion of the address Earl Derly,

proposed a vote of tbanks to the new president. This was
seconded by the Mayor, and carried with great enthu-