CONTAGIOUS DISEASES OF ANIMALS. 
3 
be a doubt that this is a contagious disease, and I feel that I can 
no longer rationally doubt it is caused by the infinitessimal germ 
—bacillus tuberculosis —recently discovered by Koch. The fact 
that this scourge is common to man and a large class of domestic 
and wild animals places it on a height of sanitary importance, and 
forbids us to ignore it, or to contemplate it with feelings other 
than those of dread and apprehension. The vital statistics of New 
York city show that 29 per cent, of the mortality of its adult 
male population is from tuberculosis, and our examination of the 
herds that supply that city with milk reveals the astounding fact 
that in certain herds tuberculosis affects 20, 30, and in some cases 
50 per cent. Nor is this the worst showing that can be adduced. 
I have seen single herds of fifty and sixty I ead in the healthy 
country districts of New York in which 90 per cent, are the 
victims of tuberculosis. 
Experience has shown that this disease is propagated not only 
by direct inoculation, but bv the consumption of the tuberculous 
flesh and milk and by the inhalations into the lungs of the viru¬ 
lent particles diffused in the atmosphere in water and spray. Nor 
does this complete the list of its channels of infection. I have 
recently witnessed in the biological laboratories of Europe the 
artificial cultivation of the tubercle bacillus on the freshly-cut 
surfaces of fruits and on sterilized bread, as well as ou gelatinous 
preparations, and have seen the brute sufferers from tuberculosis 
that have been inoculated from these cultivations. In the face of 
these evidences that we and our animal possessions are liable to 
contract this fatal malady by the various channels of simple skin 
abrasions, injection with our food, animal and vegetable, and in¬ 
halation with our breath, no one will accuse me of underrating 
the 
Magnitude of the Danger , 
nor of seeking to undervalue any available measure for its re¬ 
striction. One stands in wonder that in this conclusion of the 
nineteenth century the subject should still be comparatively un¬ 
noticed and untouched by governments and by their local and 
national boards of health. 
But great as is the need of sanitation in this field, and strongly 
