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it are too lengthy to find a place in this short paper. Suffice it to 
say, that of the cases treated annually by M. Pasteur, and which 
average from fifteen hundred to two thousand, the mortality is only 
1.16 per cent., a very striking result, when we consider that without 
treatment, the mortality among persons bitten by rabid animals 
is from fifteen to twenty per cent. 
In my own opinion the element of uncertainty as to the 
success of the treatment is very great, and few of us, I imagine, 
would care to be inoculated with even attenuated rabic virus. It 
is therefore a race, so to speak, between the strong and the 
weakened poison, and the result necessarily depends greatly upon 
the situation of the bite, and its proximity to the nerve centres. 
The risk of infection frcm the bite of a rabid animal is of course 
enormously greater if the person is bitten on a naked surface, 
such as the face or hand, as the virus is almost sure to be wiped 
off the tooth if the sufferer is bitten through the clothes. I should 
like to mention, though it hardly belongs to the subject, that 
common lunar caustic is not a good remedy, but that a strong 
solution of corrosive sublimate, or even carbolic acid, is much 
more effectual in destroying the germs of rabies. 
To M. Pasteur, among others, we are indebted for the know- 
ledge that infectious disease is due not so much to the pre- 
sence of the microbes themselves, as to specific poisons which 
they generate in the system, and which are of the nature of 
poisonous alkaloids or ptomaines. The chemical action produced 
by these microbes in the system is analogous to the action of the 
yeast ferment on beer or wine; the method, however, in which 
this action is produced is at present unknown. If the diphtheritic 
bacilli, for example, are cultivated, the chemical poison which they 
generate may be separated from the microbes themselves, and one 
drop of this poison injected into an animal is as fatal in its results 
as inoculation with the diphtheritic bacilli; aconclusive proof 
that it is the poison generated by the micro organism, and not the 
microbe itself, which causes the disease. 
All micro organisms are classed under the generic terms bacteria, 
microbes, and germs, and are of a vegetable nature, minute species 
of fungi; they consist of the plant itself or germ, and the seed or 
spore, which latter is of an especially hardy character, and is far 
more capable of resisting the action of germicides than the parent 
germ. Germs are of a very elementary structure, propagated 
either by means of spores or by a process called fission, that is to 
say, the parent germ divides and forms two germs, which are again 
capable of subdivision. The speed with which these germs mul- 
tiply is truly marvellous, and is said to be at the rate of a hundred 
thousand, or even more, in a single hour. It is estimated that the 
