View report page

233
sea from the two outfalls, by the two sludge ships, in twelve
months to March 31st last, was about 497,000 tons, or an average
1500 tons per week, only 77,000 tons coming from the southern
outfall. In addition to the above outlay for precipitation, £24,560
was spent last summer in deodorising operations at the outfalls
and storm overflows, the chemicals used being 1654 tons of
manganate of soda, and 749 tons of sulphuric acid. The
Committee have made arrangements "by which the whole of the
sewage at Crossness will, during the present summer, be stored in
the precipitating tanks during flood-tide, and will be allowed to
run into the river at ebb-tide only." The Committee believed
that this arrangement would be found to be very beneficial during
the hot weather—a belief that would appear not to have been
realized.
From what has gone before, it will have been inferred that the
best authorities are unanimous in the view that the sewage, crude
or after precipitation, must ultimately be taken to the land. At
Paris, it is stated that 5000 gallons, on an average, are applied to
the acre. At this rate 30,000 acres would be required for irrigation
purposes, were all the sewage of London, averaging 150 million
gallons daily, disposed of in this manner. A larger proportion of
a partially purified effluent, presumably, might be used, thus
reducing the amount of land required. The land, however, has
yet to be found, and in any case a large outlay would be required
on main and branch sewers, &c. Projects for conveying the
sewage to the land have been before the public for thirty years and
more, and nothing has been done. Probably it will be long before
anything will be done. The questions remain, therefore, Is the
river of necessity to continue to be polluted as heretofore ? Is
there no alternative? These questions were attempted to be
answered in my last Report, wherein (at pp. 189—192) I described
three schemes which had then lately been put before the public,
viz., the Amines Process, the International Sewage Purification
Process, and the Webster Electrical Process. The two last-