GATE STRUCTURES EOR IRRIGATION CANALS. 

 PROPORTIONAL DIVISION BOXES. 



27 



In parts of Utah and northern Colorado and in other places in the 

 West a type of structure is used which is supposed to divide what- 

 ever water there is in a ditch in a proportional manner. As a rule 

 this division box is used on rather small ditches, owned by a few 

 men as partners or a small group of men organized as a cooperative 

 company. The general manner of division is the same in either case. 

 Assume the organization to be a small cooperative company in which 

 a share of stock entitles the holder to the same proportion of what- 



Fig. 5. — Wooden division, box, Montana. 



ever water is turned into the ditch as one share bears to the total 

 number of shares in the company. Assume the total number of 

 shares of stock to be 36 and that the first stockholder on the ditch 

 has 11 shares and the second one 8 shares. The first division box, 

 therefore, is to turn out eleven-thirty-sixths of whatever water is in 

 the ditchj and the second box is to turn out eight-twenty-fifths of 

 the remaining water. The denominator becomes 25 for the reason 

 that after delivering water to the 11 shares the water remaining in 

 the ditch represents 36 less 11, or 25 shares. This procedure is car- 

 ried out to the end of the ditch. 



