GENEKAL PATHOLOGY. 61 



ends, to transfer the poison of Scarlatina, into the veins of 

 a Einderpest subject. 



Except in a few cases where vaccination may have intro- 

 duced, in addition to the specific virus of the Pest, some 

 typhoid germs, the inner surfaces of the viscera do not 

 exhibit evidences of the degeneration peculiar to typhoid 

 fevers, or observable in the muco-enteritis of cattle ; nor do 

 the respiratory organs reveal serous effusion, as in typhoid 

 pleuro-pneumonia. Dr. Tucker in his report to the Lord 

 Lieutenant of Ireland, while repudiating any theory of iden- 

 tity, says : *' The purple gum, the black, saltless blood, and 

 some other symptoms of the African typhus, may be recog- 

 nized in the Einderpest." Why might not a parallel be 

 drawn also with cholera, and influenza ? The answer to this 

 and the refutation of all the fanciful conceptions to which 

 we have alluded, is given by science, which has very recently 

 exploded the old classification of diseases, and has grouped 

 those which we have mentioned, with many others,* in one 

 leading class of zymotic diseases (order, miasmatic). 



The word Zymotic is derived from the Greek of ferment, 

 and was first suggested by Dr. Wm. Farr to indicate that 

 diseases, so named, manifest in their course a destructive 

 influence on the circulating medium, approaching as near as 

 may be to fermentation, and due to the action of specific 

 poisons of organic origin. These, like inorganic poisons 

 introduced into the system, are found to obey certain general 

 laws; first, that each has a specific action, and secondly, lies 

 latent in the system a certain though varying period of time, 

 before its specific action is evinced; and thirdly, that the 

 phenomena resulting from such action vary with the amount 

 of poisonous matter taken into the system, and the receptivity 

 of the patient. 



The miasmatic order of this class, as applied to the diseases 

 of cattle, may be understood to embrace all diseases which 

 are commonly ascribed to paludal or animal malaria^ all due 



* Such as chicken-pox, measles, quinsy and diphtheria, croup and hooping cough, ague, remit- 

 tent, continued and yellow fevers, ophthalmia, erysipelas, hospital gangrene and childbed fever, 

 plague and carbuncle, dysentery and diarrhoea, &c. 



