Cleae Steeams anb build Fish-passes. 379 



York and the vast West, especially those waters running 

 northward and eastward, all of which may, with a trifling ex- 

 pense, be made alive with shining shoals of the mighty sal- 

 mon and the beautiful speckled trout. 



It is also important to assist the propagation of other food- 

 fishes by artificial means. Legislatui-es should appropriate 

 sums for these pressing objects, which not only cheapen 

 meats, but add to the variety of food a source of health as 

 well as luxury, and so cheapen it as to bring it within the 

 means of all. 



Next in importance to artificial propagation is the purify- 

 ing of rivers from the numerous pollutions incident to a care- 

 less procedure in manufacturing, where poisonous minerals, 

 tan-bark, sawdust, etc., drain into the streams, instead of be- 

 ing conducted away from them or consumed. Commensurate 

 in importance Avith the purification of the rivers are properly- 

 constructed fish-passes, to enalale a salmon to surmount dams 

 and falls to reach their spawning-pools at the heads of streams, 

 for without such means procreation can not go forward, and 

 of the first stock few may be taken in the same river, but 

 the greater number will seek more accessible spawning-beds 

 at the heads of other rivers. 



Of the numerous reasons in favor of artificial propagation, 

 the following are not the least important : 



It has been proven by experiment that of salmon not more 

 than one in a thousand hatched naturally arrive at maturity. 

 Of trout, it is probable that double that proportion mature, 

 for the present experiment of propagating trout and salmon 

 side by side in Australia proves that trout thrive best, and 

 are what Lord Dundreary would call " the most wobust." 

 But the ranks of the speckled beauties in our trout-streams 

 and ponds have been eliminated, and require filling up. This 

 can not be done without the assistance of art. Let us sup- 

 pose that a pond which is supplied by streams suitable for 

 spawning is stocked with five hundred trout, each of which 

 weighs a pound. In the course of one season they will de- 



