THE IRRIGATION AGE. 



213 



above. 



to $20 under a large contract and about $30 if made 

 singly. The plate with the openings and slides can be 

 bought already made for $12 from foundries in the 

 vicinity of 

 the places 

 the hy- 

 drant is 

 used. The 

 gate can be 

 any of the 

 usual types 

 of slide 

 gate. 



The aver- 

 age of all 

 tests made 

 of this hy- 

 d r a n t 

 showed the 

 amounts in 

 being carried 

 through the open- 

 ings to be 1 per cent 

 more than their area 

 in square inches. 

 This difference in- 

 cludes all errors in 

 the measurements so 

 that these openings 

 are seen to be very 

 accurate. The tests 

 showed all openings 

 or combinations of 

 openings to be 

 equally accurate. 

 The box will there- 

 fore measure as ac- 

 curately as is re- 

 quired. The open- 

 ings are not as 

 closely adjustable to 

 the amounts turned 

 out, however, as they are in the case 

 of the box of the Riverside Water Co. 

 The gage hydrant (Figs. 5 and 6) 

 has been developed, and, so far as is 

 known, is only used by the Gage Canal 

 Company of Riverside, Calif. The 

 main box is of. mortar 2 inches thick 

 and is made in the material yard and 

 seasoned before setting. The con- 

 crete is made of 1 part cement and 3 

 parts coarse sand, mixed quite dry 

 and thoroughly tamped. The bottom 

 is cast separately and the top cemented 

 to it in the field. The dimensions of 

 the box are shown in the drawing. 

 The weir crest consists of % -inch by 

 1 ^2-inch iron cemented to the sides, 

 giving a final opening of 10 inches 

 wide and W 1 /. inches high. One man 

 makes 2 boxes in a day. In making 

 one box 2-2/7 sacks of cement are 

 used. The company charges $10 per 

 box. with weir, not installed. The 

 outlet chamber into which the water goes after passing 

 over the weir is omitted from the drawing. In the hy- 

 drant installed at Davis a half section of 18-inch pipe 



Fig. 5 Drawing of Gage hydrant. 



is used for this purpose, as shown in the photograph. 

 When the hydrant is not in use the valve shown in the 

 drawing at the end of the pipe is kept closed. When 

 in use the valve is opened to the desired extent and 

 the water rises from the valve and flows over the weir. 

 The mount flowing is determined by measuring the 

 depth of the water in the box above the crest of the 

 weir and either figuring the discharge or taking it from 

 a table. The depth of water on the crest is usually ob- 

 tained by measurement from a bracket set level with 

 the crest at the back side of the box. After the water 

 passes the weir it can be caught in various ways and 

 carried to its point of use. Generally this is done by 

 letting it fall to a pipe below and carrying it through 

 pipe distributing systems or directly into a distributing 

 flume. 



In the tests with this hydrant it was found that the 



amount of water 

 discharged for any 

 given depth was 

 greater with this 

 box than it would 

 be with a standard 

 10-inch weir. This 

 is due to the near- 

 ness of the sides of 

 the box to the sides 

 of the weir and to 

 the velocity condi- 

 tions in the box. 

 The amount of this 

 difference increases 

 as the head in- 

 creases, being as 

 much as 35 per 

 cent at the higher 

 heads. In practice 

 the principal source 

 of error in using 

 this box will be the 

 difficulty in meas- 



Fig. 6 Photograph of Gage hydrant. 



I2"cement 

 pipe 



Fig. 7 Drawing of Riverside measuring box. 



uring the depth over the weir closely. In the tests 

 this was done with special gages enclosed in stilling 

 cans, but even then it was difficult to get the depths 



