274 WHAT I KNOW OF FAEMWG. 



communities, and that our youngest cities and man- 

 ufacturing villages may wisely consider it deeply, 

 with . a view to its ultimate if not early imitation. 

 That we are not prepared to incur the inevitable ex- 

 pense of a thorough system of sewerage with reference 

 to the application to the soil of all the fertilizing 

 elements that a city would gladly spare, by no means 

 proves that we should not consider and plan with a 

 view to the ultimate creation and utilization of 

 Sewage. 



XLYI. 



MOEE OP IRRIGATION. 



I HAVE thus far considered Irrigation with special 

 reference to those limited, yet very considerable dis- 

 tricts, which are traversed or bordered by living 

 streams, and, having a level or slightly rolling sur- 

 face, present obvious facilities for and incitements 

 to the operation. Such are the valleys of the Platte, 

 and of nearly or quite all its affluents after they leave 

 the Rocky Mountains ; such is the valley of the upper 

 Arkansas ; such the valleys of the Smoky Hill and the 

 Republican, so far down as Irrigation maybe con- 

 sidered necessary. Irrigation on all these seems to me 

 inevitable, and certain to be speedily, though capri- 

 ciously, effected. 



I believe a dam across either fork of the Platte, at 



