THE SALMON 207 
partridges and pheasants, the animals show no inferiority to 
wild ones in their powers of self-protection. 
Balancing the pros and cons upon this important question, 
the conclusion to which most men have come after giving full 
consideration to the problem is that a hatchery, conducted on 
such an adequate scale as will ensure the annual dismissal of a 
large number of smolts to the sea, must be of direct advantage 
to the fishery, provided the ova can be secured without 
disturbing the fish on the natural spawning beds. But any- 
body who has witnessed the vast numbers of smolts, born and 
reared without the aid of man, which descend our rivers every 
spring, must be driven to the conclusion that, in order to have 
any appreciable effect upon the stock of salmon, artificial 
hatching must be conducted upon a very extensive scale. 
German pisciculturists conduct their operations upon a calcu- 
lation that, out of every thousand smolts which are liberated, 
three may return to the river as adult salmon. Therefore in 
order to increase the run of salmon by one hundred fish in 
a season four or five years hence it is necessary that 300,000 
smolts should be reared and set free. It is certain that this is 
far beyond anything that can be undertaken by any existing 
hatchery in the United Kingdom. It would tax the resources 
of any one of them to liberate as many fry, which, as I have 
endeavoured to show, is a fruitless proceeding. I am of 
opinion, therefore, that the money at present spent in salmon- 
hatcheries in this country would be better applied in providing 
protection to spawning fish, and in constructing dams on 
natural lakes for the purpose of flooding the rivers in time of 
drought to enable fish to ascend to the upper waters. 
In connection with the artificial propagation of salmon, 
reference may be made to the experiment at present in progress 
Rea ee for restoring salmon to the Thames, where at one 
ofSalmontotime they abounded. Two causes combined to 
the Thames. ; Z : : 
effect the extirpation of this valuable fish in the 
principal English river—first, the erection of navigation weirs 
