EXPERIMENTAL PATHOLOGY. 
423 
The chemical composition of the water containing them 
has no perceptible influence upon the duration of the life of 
pathogenic microbes, and their term of life is the same whether 
living in strictly pure distilled water, or in water more or less 
loaded with organic matters. 
Their conclusions are that water otherwise quite chemi¬ 
cally pure, which have become contaminated by the presence 
of pathogenic microbes, do not offer any better guarantee of 
inocuousness than waters more loaded with organic and inor¬ 
ganic elements ; a point of the highest importance in its rela¬ 
tion to the subject of general hygiene. And again, respecting 
most of the pathogenic microbes, their existence in water does 
not produce any noticeable change in their virulency, with 
perhaps one exception, the single exception of the bacillus of 
tuberculosis.— Archiv. de Med. Exp. 
ACTION OF RABID VIRUS INTRODUCED EITHER IN THE 
SUBCUTANEOUS, CELLULAR OR IN OTHER TISSUES. 
By C. Helman. 
The author concludes, from the absence of rabid virus in 
the blood, lymphatic glands, etc., that this virus cannot be 
cultivated except in the nervous substance, and that it gives 
rise to infection only when it is introduced by inoculation di- 
reetly into the nervous cells, or when it is not prevented from 
entering by the other tissues. Introduced and localized in 
the sub-cutaneous tissue, it does not give rise to infection; re¬ 
maining in the cellular tissue, it may give immunity. The 
degree of immunity is in direct ratio to the quantity of fresh 
virus introduced. From experiments made on dogs, rabbits 
and monkeys, by Helman, he concludes that infection de¬ 
pends not on the part of the body where the injection is made, 
but on the kind of tissue reached by the virus. Strong doses 
of virulent matter, which, if introduced into the cellular tis¬ 
sue would give rise to immunity, will very often produce 
rabies if injected into the muscular substance. Preventive 
inoculations of effective virus are a great deal less dangerous 
to man than to animals, because there is no cutaneous muscle 
in man where the inoculation is made. Those inoculations 
