PBEFACE. VU 



— powers whicli are greater because we have a 

 combination of two elements, both land and 

 water, helping and encouraging each other in 

 the work of reproduction — and where the best 

 species of fish, as salmon and trout, can be cul- 

 tivated, it is capable of yielding a revenue very 

 far exceeding that of land alone. 



Water requires few or none of those expenses 

 demanded on land. Left to itself, it produces 

 and reproduces to a degree which, computing 

 by' acreage, very far transcends the land. What 

 would our rivers and streams be worth if brought 

 back only to a state of nature, if man had 

 not (instead of cultivating them) almost de- 

 stroyed them? But ought we to be satisfied 

 to restore our streams to their natural state, and 

 content to leave them so? Is water-culture so 

 difiicult a study, so recondite in its secrets, so 

 partial and uncertain in its results, that it should 

 not vie, by the means of study and experiment, 

 with agriculture? Surely the results already 

 obtained do not tell us so ; much rather do 

 they encourage us to pursue our inquiries, that 

 we may win from Nature her secrets and 

 profit thereby. We know something of the 



