SPLENIC OR PERIODIC FEVER OF CATTLE. 127 



the soil and vegetatiou on wliicli they are fed, and tlie water wliicli they 

 drink. 



Thirdly. That their systems are charged with poisonous principles 

 which accumulate in the bodies of acclimatized animals that enjoy an 



immunity. 



Fourthly. That southern cattle may be driven so that they improve 

 in condition; and yet for some weeks, and probably not less than three 

 months, they keep excreting the deleterious principles which poison the 

 cattle of the States through which the herds are driven, on their way 

 north or west. 



Fifthly. That all breeds of cattle in States north of those on the Gulf 

 coast, without regard to age or sex, if they feed on grass contaminated 

 by southern droves, are attacked by the splenic fever ; that the disease 

 may be, but is very rarely, propagated through the feeding of hay. 



Sixthly. That the disease occurs mainly during the hot months of 

 summer and autumn and never after the wild grasses have been killed 

 by frosts, until the mild weather in spring returns; that then the grasses 

 are healthy, and continue healthy, unless fresh droves of Texan or of 

 Florida cattle are driven over the land. 



Seventhly. That heat and di'ought aggravate the disease in individual 

 animals. ^ 



Eighthly. That there is not the slightest foundation for the view that 

 the ticks disseminate the disease. 



Ninthly. That the splenic fever does not belong to that vast and 

 deadly group of purely contagious and infectious diseases of which the 

 rinderpest, the lung plague, and eruptive fevers are typical. 



Tenthly. That it is an enzootic, due to local influences, capable of only 

 a limited spread, and analogous or identical with the black water of 

 various parts of Europe. 



Eleventhly. That, however warm the weather may be, cattle affected 

 with spleni(i fever have not developed in their systems any poison like 

 the anthrax poison; and that the flesh, blood, and other tissues of 

 animals are incapable of inducing any disease in man or animals. 



Twelfthly. That splenic fever is not malignant typhus or typhoid fever. 

 That it has no anah)gue among human diseases, but is, however, devel- 

 oped under conditions which prevail where the so-called malaria injuri- 

 ously affects the human health. 



CURATIVE TREATMENT. 



The great majority of epizootic and enzo{)tic diseases never can, and 

 never will, be arrested bv the medical treatment of the sick. Even the 

 benignant epizootic aphtha', which is rarely fatal, spreads rapidly through 

 a coumtry ; and, in the long run, owing to the certainty and rapidity of 

 its transmission, entails more loss than some of the most fatal diseases. 

 Splenic fever may be classed among the incurable maladies, inasmuch 

 as we know of no antidote to the mysterious poison inducing it; and, 



