122 
IOWA ACADEMY OF SCIENCE 
water supply for the city of Altoona is from surface streams and 
reaches the city by gravity. The water is collected into reservoirs, 
and from these the water is distributed to the city. The elimination 
of most organisms is brought about through the action of sedi- 
mentation. Taking the death rate for typhoid fever from 1898 to 
1901, we find that it varies from 9 to 31 per hundred thousand, and 
for most years it was below 20. The typhoid fever death rate for 
a few cities is as follows. These figures were at the rate of per 
hundred thousand. Some of these cities are traversed by railways. 
The death rate for Boston is 26 ; New Orleans, 49 ; Columbus, Ohio, 
51; New York, 19; Detroit, 18; Denver, 30; Hartford, Conn., 58; 
Milwaukee, 18; Chicago, 31; Pittsburg, 122; San Francisco, 31; 
St. Louis, 31; Washington, D. C., 66; Wilmington, Del., 38; Louis- 
ville, 60; Philadelphia, 51; Minneapolis, 42. 
Mr. Alvord has given the following table showing the population 
in 1900, source of the water supply, and approximate mileage of 
railroads, and the number of stations: 
City 
Population 
in 1900 
New Y"ork 
3,350,000 
Boston 
560,000 
Baltimore 
508,000 
San Francisco 
342,000 
Providence, R. I 
175,000 
Kansas City 
163,700 
St. Paul 
163,000 
Rochester, N. Y 
162,000 
Denver, Col 
133,850 
Worcester, Mass 
118,400 
New Haven 
108,000 
Fall River 
104,800 
Omaha, Neb 
140,000 
Scranton, Pa 
102,000 
Cambridge, Mass 
92,000 
Grand Rapids 
87,500 
Richmond 
85,000 
Hartford, Conn 
80,000 
Trenton, N. J 
75,000 
Waterbury 
45,800 
Mobile 
38,400 
Source 
Croton River 
Nashua River, Sud- 
bury and Cochituate 
Gunpowder River 
Lake Merced, moun- 
tain stream 
Pawtucket River 
Missouri River 
Small lakes 
Hemlock lake 
South Platte 
Lynde Brook 
Mill River 
Watuppa Lake 
Missouri River 
Roaring Brook, Oak 
River 
Stony Brook 
Grand River 
James River.. 
(Brooks) 
Delaware River 
(Ponds) 
Clear Creek 
Approximate Mileage 
of Railroad and No. 
of Stations 
45 miles railroad, 18 
stations 
34 miles • 
38 miles parallel, 41 
stations on map 
None 
10 miles, 10 stations 
Over 300 mil6s in im- 
mediate vicinity 
No railroad 
No railroad, summer 
resort around lake 
75 miles, 14 stations 
No railroad 
35 miles, 10 stations 
5 miles, 3 stations 
210 miles below Sioux 
City, 12 stations 
10 miles 
5 miles 
260 miles, 70 stations 
150 miles parallel, 92 
stations 
15 miles, 4 stations 
100 miles parallel 
No railroad 
No railroad 
