1292 BULLETIN OF THE BUREAU OF FISHERIES. 



the lakes as a knowledge of soil physics and chemistry is to the best agricultural 

 use of the land. The problems of the lakes are complex and are not easily 

 solved, but they are far less complex and much more easily solved than are the 

 corresponding problems of the soil. This nation and the several states are 

 spending hundreds of thousands of dollars annually in studying the soil. This 

 expenditure is fully justified, not only by its scientific results but also by its 

 practical consequences. Little or no time or money is now devoted to the 

 similar study of the waters of the lakes. Yet no one who has followed investi- 

 gations of this kind can doubt that if the lakes could be studied on the same 

 large scale and with the same careful methods as those applied to the study 

 of soils, results of great economic value would be obtained. It was years before 

 the study of physics and chemistry of soils promised large economic results. 

 Valuable practical hints have already come from the brief and imperfect study 

 of the lakes which our survey has made, and the present situation of our knowl- 

 edge indicates that a wider and more systematic study than we have been able 

 to undertake would ultimately lead to far larger and more important con- 

 clusions. Such a study is greatly needed. The culture of fish in the innumer- 

 able inland lakes of this country should rest on the basis of scientific knowledge 

 at least as broad and as complete as that which underlies the cultivation of our 

 farm products. We who have in charge the maintenance of a public interest 

 so extensive and valuable as is that of the fisheries are most of all concerned 

 in the acquisition of that knowledge which is the only true guide of practical 

 affairs. 



