372 THE POPULAR SCIENCE MONTHLY. 



filth-disease, arises largely from indigestion, and forms the basis, so to 

 say, or is in fact the first stage of all the so-called filth-diseases. 

 Whatever interferes with digestion or depuration, or depraves the 

 vital organism in any manner, produces an impure condition of the 

 body a condition of disease ; and a continuance of disease-producing 

 habits must inevitably result in periodical or occasional " eruptions," 

 the severity of which will depend upon the degree of one's transgression. 

 Among the causes of this impure bodily condition are (1) impure 

 food,* (2) excess in diet, and (3) impure air. Our homes, oftices, 

 shops, halls, court-houses, churches, and, with rare exceptions, all liv- 

 ing-rooms, private or public, are insufficiently or not at all ventilated ; 

 and, except while in the open air, a very large proportion of our 

 people, in all the walks of life, habitually breathe an atmosphere viti- 

 ated by being breathed over and over again ; they are starving for 

 want of oxygen, and are being poisoned by carbonic acid. In default 

 of sufficient oxygen the best of food can not be transformed into pure 

 blood there will always be a corresponding indigestion ; nor can the 

 carbonic acid be eliminated freely in an impure atmosphere. We 

 have, then, serious " interference with digestion and depuration," 

 whenever we remain even for a single hour of the twenty-four in an 

 " in-door " atmosphere, i. e., an atmosphere that is not in tolerably free 

 communication with the great body of air without. The only offset 

 for restriction in oxygen is restriction in diet and exercise ; but a com- 

 bination of this character would produce enfeeblement of the system, 

 though if a proper balance were maintained there would arise no 

 febrile symptoms such as we are considering. We have plenty of 

 people living in unventilated rooms who, so far as exercise is concerned^ 

 live a well-balanced life ; but seldom do these, any more than the 

 robust and active, practice any sort of voluntary restriction as to 

 quality or quantity of food nausea and lack of appetite being the 

 only safeguards. Persons of this class are great sufferers from colds. 

 Impure air, although a prevailing source of disease, is not abso- 

 lutely essential in provoking this disorder ; an unwholesome diet alone 

 being sufficient. In none of my own experiments have I suffered any 

 restriction in the matter of pure air. But for this depraved condition 

 this chronic state of impurity that I have undertaken to describe 



* Under this head I am led to class all foods eaten unnaturally, as (1) farinaceous 

 dishes (the mushes, soft bread, etc.), that on account of their mode of preparation and 

 dressing can not be insalivated ; and (2) flesh-food that is " well masticated " or taken 

 in the form of hash. It has been demonstrated (by experiments on dogs) that carnivo- 

 rous animals fed on hashed meat suffer from indigestion, while, if they are allowed to 

 swallow their meat as they like, in chunks, it is all digested. In repeated experiments 

 upon myself, I find that a moderate ration of meat, swallowed in pieces of convenient 

 size, occasions no disturbance, while the same quantity chewed fine, or taken in the form 

 of hash, is not well borne. The point is, that while minced meat passes out of the stom- 

 ach before being dissolved by the gastric juice, large pieces remain to be gradually 

 dissolved. There is no demand for the chemical action of saliva on this class of foods. 



