IOWA ACADEMY OF SCIENCE 
123 
However, that typhoid fever can be occasionally spread through 
carelessness on the part of railroads has been made evident in the 
report of typhoid fever in Butler, Pennsylvania. The city of Butler, 
with a population of 18,000, is situated in Butler County on a little 
creek 39 miles from Pittsburg, with an average elevation of 1,050 
feet above sea level. The country is sparsely settled several rail- 
roads enter the city. The water is derived from private wells, the 
Butler Mutual Water Association, and the Butler Water Company. 
A mechanical filter plant was established in 1902. The filters con- 
tain six inches of gravel and three and a half feet of natural sand. 
During a part of the epidemic, this filter plant was not in operation. 
It was shown on investigation that there were several cases of 
typhoid fever in families living near the reservoirs on Thorn Run 
and Boydstown. Bacteriological examinations revealed that the 
number of organisms was not large, generally below 1,000, but in 
a few instances from 14 to 50,000. In a few cases, the colon bacillus 
was found. The watershed comprises 28,217 acres; it is sparsely 
settled at the rate of about 24 persons per square mile. The place 
is broken and hilly, and the run-off of water very rapid. Near the 
head waters is located a little village called Greece City. An investi- 
gation of the entire watershed showed that not only had typhoid 
fever existed at various points within its boundary, but in 1902 the 
unusual number of 14 cases had occurred, and in 1903, 17 cases co- 
incidently in the months of September and October. Three of 
these died. In 1903, the cases were divided among eight families; 
two of the cases occurred within 1,500 feet of the intake at the 
pumping station. The probable source of infection in the cases in 
close proximity to the pumping station was a well within 200 feet 
of the house, and partially underlying the tracks of one of the rail- 
roads. The source of infection in the four cases existing in Sep- 
tember in close proximity to the Thorn Run reservoir originated in 
the person of a visitor from a distant section of the State. It was 
found, further, that the train crews and men to the number of 70, 
working on the railroad made use of the numerous privies found in 
close proximity to the stream and that this may have helped to 
spread the disease. 
Prof. Roberts, in speaking of the drainage area of Seattle, says : 
“Cedar River, from which Seattle derives her water supply, has 
a tributary drainage area at the intake dam of 150 square miles; 
at the power dam at Cedar Lake 75 square miles. With an annual 
rainfall, over the entire area, approximately 100 inches. The area 
