History of the Water Supply of the World / arranged in a comprehensive form from eminent authorities, containing a description of the various methods of water supply, pollution and purification of waters, and sanitary effects, with analyses of potable waters, also geology and water strata of Hamilton county, Ohio, statistics of the Ohio river, proposed water supply of Cincinnati.

by Thomas J. Bell

REDUCTION OF SEWAGE BY AERATION.

One volume of filtered London sewage mixed with nine volumes of water, the mixture contained .267 organic carbon and .081 organic nitrogen. After agitation and freely exposed to the air and light every day, and being syphoned, in a slender stream, from one vessel to another, the result, after 96 hours, was .250 organic carbon, and .058 organic nitrogen; and, after 196 hours’ test, was .2 organic carbon, and .054 organic nitrogen. Temperature, 20° centigrade.

The above results would correspond to a flow of 96 miles, at rate of one mile per hour, with a reduction in per cent of 6.4 organic carbon, and 28.4 organic nitrogen; or a flow of 192 miles, at rate of one mile per hour, with a reduction in per cent of 25.1 organic carbon, and 33.3 organic nitrogen.

Test of a mixture of fresh sewage with Thames water, and enclosed in stopped bottles, and opened to air at following intervals, with results opposite the respective periods:

	PER CENT OF SEWAGE DESTROYED.
1. Period of 24 hours	6.8
2. Period of 24 hours	8.9
3. Period of 48 hours	14.3
4. Period of 24 hours	5.4
5. Period of 24 hours	5.8
6. Period of 24 hours	2.1
	——
Total	43.3

Dissolved oxygen contained in the enclosed water was determined by boiling off the dissolved gases.