354 POPULAR SCIENCE MONTHLY. 



is good reason to believe that the bacillus of bubonic plague may be 

 transmitted in the same way. The cholera spirillum is quickly killed 

 by desiccation and this disease is probably very rarely, if ever, com- 

 municated through the medium of dust. But the germs of typhoid 

 fever and of bubonic plague are more resistant and, without doubt, 

 under certain circumstances, these diseases are extensively propagated 

 by means of dust containing desiccated excreta. There is a good reason 

 to believe that in several of our camps, during the Spanish-American 

 War, this was an important factor in the etiology of typhoid fever epi- 

 demics. The average mortality from typhoid fever in our regular 

 army since the Civil War has been, for the first decade (1868-1877) 

 95 per 100,000 of mean strength; for the second decade (1878-1887) 

 108 per 100,000, for the third decade (1888-97) 55 per 100,000. This 

 latter rate compares favorably with that of many of our principal cities ; 

 for example, it is exceeded by the typhoid death-rate of the city of 

 Washington, which is 78.1 per 100,000 (average of 10 years, 1888- 

 1897), by that of the city of Chicago, which is 64.4 per 100,000; by 

 that of Pittsburgh, which is 88 per 100,000. As a result of insanitary 

 conditions existing in the camps in which our troops were hastily 

 assembled at the outset of the Spanish-American War, the typhoid 

 death-rate in our army of volunteers and regulars during the year 

 ending April 30, 1899, was more than 22 times as great as it had been 

 in our regular army during the decade immediately preceding the war 

 period. As compared with the Civil War, however, there was a decided 

 improvement, the typhoid mortality for the first year of the Civil War 

 having been 1,971 per 100,000 of mean strength and for the Spanish- 

 American War 1,237 per 100,000. 



Experience shows that new levies of troops are especially subject 

 to typhoid fever and other infectious 'camp diseases,' not only because 

 of lack of discipline and consequent difficulty in the enforcement of 

 sanitary regulations, but also because the individual soldiers are very 

 susceptible to infection, owing to their age, the abrupt change in their 

 mode of life, the exposure and fatigue incident to camp life, and last, 

 but not least, their own imprudence as regards eating, drinking, exer- 

 cise, etc. In the absence of sewers or other adequate means of removing 

 excreta, the camp site is likely to become infected by the discharges of 

 unrecognized cases of typhoid and typhoid bacilli are carried by flies 

 to the kitchens and mess-tents and deposited upon food, or as dust are 

 directly deposited upon the mucous membranes of the respiratory 

 passages of those living in the infected camp. That preventive medicine 

 has still serious work before it is shown by the fact that according to 

 the last census return there were 35,379 deaths from typhoid fever in 

 the United States during the census year 1900. The increase in mor- 

 tality over the number in 1890 (27,056) is out of proportion to the 



