AGRICULTURAL EXPERIMENT STATION. 259 



of another bacillus, differing in size and habits of growth 

 when cultivated artificially, which he calls the Swine Plague 

 bacillus, and he has been able to prove that this second germ is 

 the sole cause of the disease which he calls Swine Plague. 



Swine Plague seems not nearly so common as Hog Cholera, 

 and the symptoms of the two diseases are so nearly alike that it 

 requires an expert to distinguish between them without making a 

 bacteriological investigation. For the purposes of this article the 

 diseases will be classed together and called Hog Cholera. 



With the discovery of the cause new light was thrown upon the 

 contagious diseases of swine, and the importance of the subject 

 was sufficient to lead many investigators to turn their attention 

 to the subject, so that the woik done by Dr. Salmon and his assis- 

 tants has been repeated and verified by many others who have 

 added to the work done by the Bureau of Animal Industry. Jt 

 has been my privilage to study several outbreaks of Hog Cholera 

 in the vicinity of Baltimore where it prevails every year to a seri- 

 ous extent, and since coming here I have been called upon to 

 investigate an outbreak in this State where ten out of twelve 

 exposed hogs died. From the Baltimore cases as well as from 

 those in this State I obtained cultures of the Hog Cholera bacillus 

 with which 1 have been carrying on experiments to determine the 

 hitherto undecided point of the degree of heat required to destroy 

 the germs. 



I have found this point of difference between the Hog Cholera 

 and Swine Plague germs. The Hog Cholera bacillus will live at 

 a temperature that destroys Swine Plague. Both of them are 

 destroyed at a temperature of 57° (137° F.) when they are 

 exposed for a period of ten minutes. It is not my purpose in 

 this article to go into the details of the experiments that I have 

 conducted, as in the main they have been but a repetition of 

 experiments made at Washington, but with conditions more fav- 

 orable than could be obtained in a locality like Washington where 

 inoculation experiments are liable to be interfered with by natural 

 infection. In confirmation of the results obtained by the Bureau 

 of Animal Industry I may say that I have obtained both Swine 

 Plague and Hog Cholera by inoculation, the time taken to kill 

 inoculated animals depending on the amount of the virus intro- 

 duced. 



I wish to bring to the attention of farmers of the State such 



