234 POPULAR SCIENCE MONTHLY. 



THE END OF THE FILTH THEORY OF DISEASE. 



By Dr. CHARLES V. CHAPIN. 



Ij^OIl half a century in this country, and for a longer time in Eng- 

 -*- land, the filth theory of disease has dominated medical thought 

 and has been accepted with trusting faith by the public, particularly 

 by the better educated portion thereof. The idea that filth is the cause 

 of disease dates back to a much earlier period. It has probably been a 

 common belief among most civilized peoples. In colonial times many 

 of our physicians believed in the close connection between filth and 

 disease, and these notions sometimes found expression in laws. The 

 prevalence of yellow fever in most of our seaboard cities during the 

 last years of the eighteenth century did much to advance the filth 

 theory, for this fever was held by many physicians to be par excellence 

 a filth disease. The popular ideas were doubtless illustrated by the 

 legislation enacted in Massachusetts, which provided for the summary 

 removal of 'any nuisance, source of filth or cause of sickness.' This 

 law has since been copied by fourteen states. The filth theory, how- 

 ever, did not become the vogue until the latter half of the nineteenth 

 century. Its great popularity was largely due to the efforts of three 

 men: Chadwick in England, Pettenkoffer in Germany and Shattuck 

 in the United States, but doubtless most of all to Chadwick. Edwin 

 Chadwick was a lawyer and social reformer. He was intensely 

 humanitarian, and the misery then existent in England appealed most 

 strongly to him. He saw that the poor people were filthy and sick, and 

 he assumed that the sickness was due to the filth. There were some 

 who objected that the relationship was not proved, but their objections 

 amounted to little at a time when scientific reasoning was just 

 beginning to find a place in medical thought. The practical reforms 

 brought about by Chadwick and his followers in improved housing for 

 the poor, improved refuse disposal, the introduction of drainage systems 

 and the betterment of water supplies, certainly resulted in increased 

 comfort, and constituted a decided advance in what we call 'civiliza- 

 tion.' But they did not exterminate the infectious diseases as had been 

 hoped and promised. The filth theory found strong supporters among 

 engineers, and later among drain-layers and plumbers. These men 

 accepted honestly enough the teaching of their medical advisers, and 

 naturally became active propagandists of a theory which demanded 

 such services as they alone could render. 



