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IRRIGATION FARMING. 



The joints are connedledby means of collars, which fit 

 closely over and around the ends when united. 



Cost of Pipes. — To determine the capacity of any 

 pipe it may be well to remember that twice the given 

 diameter increases the capacity four times. The fa<5lor 

 of first cost to the pipe, while it is undoubtedly the 

 one requiring the least labor to determine, is also the 

 most difficult to arrive at with exacftness. Being sub- 

 ject to commercial laws of supply and demand, trans- 

 portation, competition, etc., this item is so variable 

 that exa(5t estimates can only be given for the present, 

 which may not be at all reliable for the future. It will 

 therefore be our aim to present estimates of cost which 

 may be taken as a fair average and will be relatively 

 corre(5l as between the different kinds of pipe. With 

 this in view the following table has been prepared, 

 which covers the sizes and kinds of pipe heretofore 

 principally used in the construdtion of piped irrigation 

 systems : 



