62 THE SALMON FISHERIES. 
their refuse, to keep it out of the rivers; even if they were 
not influenced by the reflection that the fisheries would be 
benefited thereby ; even if public health reaped no advan- 
tage, and the causes of natural beauty were not served, 
manufacturers would be the gainers by having pure water 
instead of dirty water to use. Factory owners in South 
Wales, for example, find their engine-boilers rapidly 
destroyed by the use of water from the rivers impreg- 
nated with sulphuric acid; and an enormous expenditure 
is incurred elsewhere in the country in the partial purifi- 
cation of dirty river water before it can be used for manu- 
facturing purposes, or in the sinking of wells, which would 
often be needless if the rivers were kept even tolerably pure. 
Manufacturers and mine owners, however, are not the 
only people who sin in this respect. The inhabitants of 
every town that casts its sewage into a river as the easiest 
and apparently the cheapest means of getting rid of it are 
collectively and individually to blame. It is a serious 
question whether so easy a means of getting rid of 
this and other polluting agencies may not be too dearly 
purchased. Not only are the fisheries injured or ruined, 
but public health is affected by the contamination of the 
atmosphere caused by the fermenting sewage ; the land 
is robbed of a valuable manure ; we are deprived of our 
natural supplies of pure water ; whole fields are destroyed by 
noxious waters carried over them by floods, and the very 
grass, instead of being benefited, is poisoned, so that the 
cattle that eat it are killed. Every one acknowledges now- 
adays that the proper place for the sewage is the land, not 
the water. It has already been satisfactorily shown that 
the sewage can be profitably utilised. The question is, 
how shall the principle be carried out? Irrigationists and 
precipitationists may fight over the bone if they will, and 
