57 



Althoug-li all the diseases named, except trichinis, originate from animal 

 poisons, yet they do not affect the same parts of the body and in a similar way. 

 Thus cholera is a disease of the stomach and bowels in the beginning, whilst 

 the cattle plague and small-pox origiuate in the blood. The cause of the last 

 disease must be swallowed ; of the first, inhaled into the lungs. But what is 

 this cause? Science has long sought to answer this question, but as yet most 

 vaguely, and, therefore, not satisfactorily. Still, as in the discovery of the 

 sources of the Nile, some progress is making, and although certainty has not 

 been reached, the darkness is being dispelled. 



A growing opinion is that the cause of these diseases is an atomic particle en- 

 dued with life-power, that is, to convert healthy parts of the body into its own 

 elements, or into like atoms, from which the disease originated. In cholera, and 

 perhaps in hog cholera, this atomic particle cannot reproduce itself unless it 

 effects a lodgement in the stomach, but when there it rapidly converts the 

 watery particles into numberless atoms like itself, and these, as in the fermenta 

 tion of yeast, are endued with a similar power of self-propagation. They draw 

 to themselves the watery particle of the blood in the veins, and the blood robbed 

 of this water becomes too thick to circulate. Coldness ensues, cramps follow, 

 until life is destroyed. 



The atomic particle of disease in the cattle plague and small-pox is inhaled 

 into the lungs, where it mixes with the blood and converts it into its own parti- 

 cles. And this it does for some days, called the incubation of the disease, un- 

 noticed, for it is unmarked by any outward indications of its presence. The ani- 

 mal gives no evidence that it is not in good health. But disease is antagonistical 

 to life, and when these diseased atoms become so numerous as to interfere with 

 the proper action of life, then the struggle commences between these opposing 

 forces. One must overcome the other. Nature endeavors to throw from the 

 blood these atoms of disease ; in the cattle plague or typhus fever they are 

 forced upon the internal surfaces of the stomach and bowels or lungs ; in the 

 small-pox, upon the external surfaces of the skin. In this effort to throw off 

 the disease nature often sinks from exhaustion. 



HOW THE POISON OF DISEASE MAY BE TRANSMITTED FROM THE SICK TO THE 



WELL. 



And here the inquiry presents itself, In what way do these atoms of disease 

 obtain their lodgment in those portions of the body where they are capable of self - 

 viultiplication 1 The answer tends to lead us to a useless notice of those terms 

 about which medical men have written and disputed so much — namely, contagion 

 and infection. These controversies but serve to show that even such diseases 

 as those we are considering are neither contagious nor infectious. We choose 

 rather to follow what the common sense of every person tells him is true, that 

 these and like diseases, indeed nearly all diseases, are communicable. Whether 

 this communicability is to be called contagion or infection, or by any other name, 

 is to us immaterial. We speak of this communicability when we say of the 

 cholera that it is an epidemic ; of the cattle plague, that it is an epizootic ; that 



