ATMOSPHERE IN RELATION TO HUMAN LIFE AND HEALTH. 261 



which belongs to fungoid growth. When ingested with food, and even 

 when breathed with the air, it causes the disease. The air of that 

 part of a town which was subject to diarrhea has been proved to con- 

 tain germs which cause the disease, and to contain 2,000 to 7,000 bac- 

 teria and micrococci in the cubic meter. The deaths in this part of 

 the town, containing one-third of the population, were 216 out of a 

 total of 25G. The remedies for diarrhea are principally draining the 

 ground to a considerable depth, paving, ventilation of dwellings and 

 of places where milk and food are kept with air from some height above 

 ground, cleanliness generally, and a good water supply. Cows, farm- 

 yards, and dairies need similar attention. Diarrhea is much less 

 common among the Irish population of large towns, owing to their 

 infants being almost invariably suckled by their mothers and not 

 from the bottle. 



The general air soon nullifies the danger from strata near the 

 infected ground, and the germ seems to be incapable of enduring con- 

 veyance in a potent state through any considerable distance in the free 

 atmosphere. 



TYPHOID FEVER. 



Typhoid fever, like cholera and diarrhea, depends to a great extent 

 on the growth and cultivation in neglected human refuse by human 

 agency (unwilling but effectual) of germs which thrive in damp, pol- 

 luted soil or in foul water. Warmth and exclusion from free air favor 

 the development of the bacillus, supposed to be the cause of typhoid. 

 It can grow, however, in the presence of free oxygen, and then develops 

 the saprophytic habit and great resistant power. In direct sunlight it 

 is killed in six to seven hours, and in diffuse daylight growth is very 

 slow. The mode of entrance of typhoid is both through air and water 

 contaminated with the products of the intestinal discharges of persons 

 sick with the disease. 



During twenty years preceding 1883, the average annual number 

 of persons who died of typhoid in England was about 13,000, the 

 number of those who suffered from it about 130,000. In many conti- 

 nental cities, the proportion is much higher. Although bad water 

 accounts for a large number of cases, bad air, the emanations from 

 drains through defective traps and waste pipes, also infects in very 

 many instances. Kecent experiments of great interest have shown 

 that sewer air is capable of so poisoning the system as to lay it open 

 to the attacks of the typhoid bacillus, which is doubtless frequently 

 present either in the foul air or in the intestines. In this way many 

 outbreaks are caused by the combined influence of drain air and spe- 

 cific microbes. The condition of farmyards near dairies whence milk 

 is supplied to cities is too often so filthy that both air and water are 

 poisoned. Milk has a remarkable power of absorbing gases and vapors, 

 and is also a cultivating medium of various fungi and bacteria. 



Typhoid germs, like so many others, are soon rendered innocuous by 



