14 ECONOMICS OF FORESTRY. 



of civilization, do not call for the exertion of 

 private enterprise and offer no incentive, or 

 only an imperfect one, for private action, or are 

 beyond the limits of control by private individ- 

 uals. 



Thus, if there is the possibility of influencing 

 climatic conditions by human action, which is 

 doubted by some climatologists in defiance of 

 many patent facts, it would be a matter of public 

 concern rather than of private interest to preserve 

 favorable or improve unfavorable conditions. As 

 far as the forest yields useful material for the arts, 

 it is an object of private industry ; but when, by its 

 position on a watershed, the forest becomes an 

 influential factor in the water conditions of the 

 plain, it may still serve the purposes of gain and 

 wealth, which are the objects of private industry, 

 but its indirect significance for sdciety at large 

 exceeds the private interest. 



Of the proper condition of waterways, of navi- 

 gation and transportation, it may be said, that 

 while private interest may be concerned with it 

 for private gain, public interest is involved in it to 

 a much greater extent. For private interest lies 

 only in the direction of individual gain, while state 

 interest lies in the direction of social gain, of gain 

 for a larger number. Whenever, therefore, other 

 purposes, which do not contemplate the highest 

 profitableness, are to be subserved, especially pur- 

 poses which are of interest to the community at 



