IOWA ACADEMY OF SCIENCE 
141 
3. I would further recommend that the debris, logs, etc., found 
in the river at numerous points should be removed as soon as 
possible; that the material in the swamp of Cedar Lake should be 
cleaned out and made attractive. 
4. The most dangerous time in connection with the construc- 
tion of the C., M. & St. P. Railway through the watershed would 
be at the time when the railroad is being constructed, but sanitary 
science has discovered means of effectually removing all of the 
objectionable features connected with these camps. All of the 
material can be cremated and removed, so that there would be no 
chance for infection. The city should provide sanitary inspection 
at each of the camps, and furthermore a physician should be em- 
ployed to give proper medical attendance. 
5. The railroad in passing through the watershed should have 
all toilet rooms locked, and there should be no stations permitted 
anywhere between the power plant and the city intake; that a 
road running through the city watershed will add greatly to the 
facilities for protecting and police patrolling the district later; 
that because of the excellence of the filter material, consisting of 
sand and gravel, there would at no time be any danger from the 
passage of infectious material from the right of way to the water; 
that where the distances are fifty feet and less, the drainage should 
be carried to some convenient place, and there discharged into a 
filter bed. These filter beds are efficient in the removal of all. 
organisms. It has been shown experimentally in numerous filtra- 
tion plants in the country, where sewage is disposed of in this 
way, that from 99 to 99.8 per cent of the bacteria can be removed, 
and that the conditions existing in the Cedar River watershed 
would be even greater than in the figures I have here given. 
6. I can see no reason why the C., M. & St. P. Railway should 
not be given a right of way through the Cedar River Valley, and 
believe it would not endanger the purity of the city's water supply. 
BIBLIOGRAPHY. 
Burrill, J. T. Rep. of the Univ. of 111. 97-119. pi. 22-30. 
Editorial, Engineering News, Aug. 30, 1906. 
Fuller, Geo. W., and Ferguson, C. E., concerning tests for B. Coli Com- 
munis in water. The Jour, of Infect. Diseases. Suppl. 1. 1905. 142-146. May. 
Hazen, A., 1890. Rep. of experiments upon the chemical precipitation of 
sewage at the Lawrence experiment station in 1889. Special Rep. of the 
Mass. State Board ©f Health on Water Supply and Sewerage, pt. 2, 737. 
Jackson, Daniel O. A new solution for the presumptive test for Bacillus 
Coli. Biological Studies by the pupils of William Thompson Sedgwick. 292-297. 
