744 Water in Relation to Health and Disease . 
river pollution depends very mucli upon the size of the stream 
and the volume and velocity of the current in relation to the 
quantity of polluting matter it receives. Not only so, but 
owing to the irregularity in the discharge of refuse from mines 
the degree of pollution existing at different times will be found 
to vary ; so that a stream whose water may be harmless to-day 
may, when mine water is being thrown out in large volumes, 
become dangerous to-morrow, and the danger will be materially 
increased if, as in dry seasons, the river water is low. 
It is fortunately the case that cattle and horses, as a rule, 
refuse to drink from these discoloured and offensive streams, but 
in times of scarcity of water, and of neglect to provide a more 
wholesome supply, they are driven by an overpowering thirst to 
do so and to suffer. 
Mr. Thomas Olver, veterinary surgeon of Truro, who has a 
large experience of the effects of polluted water on stock, says : — 
“ Many of the streams of water in the mining districts of Cornwall 
are polluted with refuse from mines, principally with tin and 
more or less arsenic and other minerals. I have frequently 
seen cattle which, in my opinion, have suffered from drinking it. 
They lose flesh, get hide-bound, with peculiar dry, staring coat. 
They go off their food, which generally ends in diarrhoea and 
frequently death.” 
The refuse and waste products from mills, works, and manu- 
factories which are discharged into our streams comprise a large 
and miscellaneous assortment of organic and inorganic com- 
pounds. Of the former, the waste from alcohol distilleries, many 
of which are to be found in the basin of the Tweed, possesses 
large and dangerous polluting properties, not so much in itself 
as in the products of putrefaction to which it gives rise. The 
polluting nature of the matter discharged from these places is 
best shown by reference to the following analysis, in which 
distillery waste is compared with London sewage : — 
Distillery Drainage and London Sewage . 1 
Eesults of analysis expressed in parts per 100,000. 
Dissolved Matters 
Suspended Matters 
— 
Total 
solid 
matters 
Organic 
Carbon 
Organic 
Nitrogen 
Ammo- 
nia 
Nitrogen 
as Nitrates 
and 
Nitrites 
Total 
combined 
nitrogen 
Min- 
eral 
Org- 
anic 
Distillery 
Waste 
13006 
381-173 
108-503 
2-550 
— 
110-603 
5-10 
114-00 
Average 
London 
Sewage 
1 64-6 
\) 
4-386 
2 484 
6-567 
7-06 
24-2 
20-6 
1 Report of Rivers Pollution, Commission. 
