threatens not only to decimate our animals, but to expose the human 
family to disease from the consumption of unwholesome meats.”’ 
Here was an early recognition not only of the importance of under- 
standing and controlling animal diseases, but of the still greater neces - 
sity of protecting the consumer of meats from products contaminated by 
disease and therefore unwholesome. In other words, it was a Tecog- 
nition of the growing need of meat inspection. 
THE ERADICATION OF PLEURO-PNEUMONI,A. 
The most pressing duty devolving upon the new Bureau was the 
control and eradication of the contagious pleuro-pneumonia of cattle, 
a disease which had been already the cause of restrictions upon our ex- 
ported cattle, and which, it appeared, might soon lead to the entire 
prohibition of this branch of the export trade. Notwithstanding the 
urgent demand for effective work, the authority given at first was most 
inadequate. It was not until 1887 that the Bureau was allowed to em - 
ploy a sufficient force and to use its appropriation properly for stamping 
out the disease. By this time, the contagion, which had been found 
prior to 1884 in only a few States on the Atlantic seaboard, had spread 
to Ohio, Illinois, Kentucky, and Missouri, and threatened to cover such 
a large area as to be uncontrollable. 
By hard and systematic work, however, persisted in for five years, 
pleuro-pneumonia was completely eradicated, and since early in 1892 no 
case of this disease has been discovered in the United States. This first 
work in which the Bureau was engaged was remarkable in its results, 
because it succeeded in a very few years in accomplishing what other 
countries, such as Great Britain, France, Germany, and Belgium, had 
labored for years to do, without success. 
During the period which elapsed between the creation of the Bureau 
in 1884 and the complete eradication of pleuro-pneumonia in 1892, the 
scientific work of the Bureau had been pressed forward vigorously. 
The germs of hog cholera and swine plague were discovered and care- 
fully studied, and Texas fever,the most mysterious of diseases at the 
time its investigation was commenced, was thoroughly elucidated by the 
discovery of the cause and the method of dissemination by means of the 
cattle tick. 
SCIENTIFIC INVESTIGATIONS. 
In the study of the hog cholera bacillus, it was shown that this 
germ produces some substance, in the liquids in which it is grown, 
which is capable of conferring immunity upon animals when injected 
beneath the skin. The establishment of this new principle gave an im- 
petus to the study of immunity in all parts of the world and led to the 
discovery of the various toxins and antitoxins which are now so largely 
used in both human and veterinary medicine. 
The demonstration that a contagious disease, such as Texas fever, 
was caused by one of the protozoa, and that this organism was trans- 
ferred from animal to animal by a second parasite, the southern cattle 
tick, opened up another new field in medicine, which has led to the dis- 
covery that the malarial parasite and probably the organism of yellow 
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