254 FISH CULTURE, 



possibly be beneficial in the long run, though in 

 many places it would be a very great and needless 

 hardship. It would be far better if we strove to 

 arrive at something like a definite idea of the spawn- 

 ing grounds, and the times when they were used by 

 the fish, and to prohibit any interference with thenl. 

 This, I think, is aU that is really desirable, and all 

 that any one has a right to require of us. 



But there is another circumstance, besides the 

 wasteful destruction of small fish, which is gradually 

 but surely affecting our coast fisheries. Wherever 

 mining operations are carried on, the rivers and 

 brooks are first poisoned by them and all the fish 

 killed ; and the poisoned water in turn, emptying 

 itself into the sea, carries down very strong deposits, 

 which in time, being driven about and dispersed by 

 the waves, has the effect of driving the fish off the 

 coast. One instance of this, out of many, I will par- 

 ticularize. At Aberystwith, two rivers carry down 

 from the lead mines strong poisonous deposits. 

 Twenty or thirty years ago, before the mines were 

 opened, the rivers abounded in fish, and the sea-coast 

 adjacent was abundantly supplied with many kinds 

 of sea«-fish. Within the time specified, however, they 

 have almost entirely disappeared for some miles 

 above and below this place, though plentiful enough 



