132 MICROBES, FERMENTS, AND MOULDS. 
CHAPTER IV. 
MICROBES OF THE DISEASES OF OUR DOMESTIC ANIMALS. 
I. ANTHRAX, OR SPLENIC FEVER. 
THE first of the virulent and contagious diseases in 
which the presence of a microbe was positively 
ascertained was anthrax, or splenic fever, which 
attacks most of our horned animals, and especially 
cattle and sheep. 
As early as 1850, Davaine had observed the 
presence of minute rods in the blood of animals which 
died of splenic fever; but it was only in 1863, after 
Pasteur’s first researches into the part played by 
microbes in fermentations, that Davaine suspected 
these rods of being the actual cause of the disease. 
He inoculated healthy animals with the tainted blood, 
and thus ascertained that even a very minute dose 
would produce a fatal attack of the disease, and the 
tods, to which he gave the name of Bacteridia, could 
always be discovered in enormous numbers in the 
blood. 
