Introduction 73 



the owners of the ranch, it was beHeved that no risk was being 

 taken. 



Difficulty arose, however, in obtaining the necessary equipment, 

 owing to pressure of business in the foundries of the Middle West, 

 and work was not commenced until December 14, 1916. In the 

 meantime, since it was necessary to have three miles of pipe line 

 laid by February 1, 1917, a portion of the contract was taken away 

 and re-let to a company making hand-tamped pipe. This company 

 began work about November 28, and finished pipe-making January 9. 



The conditions, therefore, were ideal for obtaining a comparison 

 between machine-made and hand-tamped pipe. Both parties were 

 experienced, both were using the same sand and cement, and both 

 were curing their pipe under absolutely the same climatic condi- 

 tions. The two methods could be compared as to speed and cost, 

 and the pipe made could be compared as to strength, perviousness, 

 and frictional resistance to flowing water. The tests were planned 

 and partly carried out, but, unfortunately, an insufficient number of 

 the hand-made pipe were held out at the time of laying. Some tests, 

 therefore, were made only on the machine-made pipe. All tests 

 made are reported later on in this bulletin. 



In the fall of 1917 the town of Glendale, Arizona, voted bonds 

 for a main sewer line and outfall sewer to New River. Bids were 

 received under the specifications for both clay and cement pipe 

 sewers. Although the specifications were more severe for the ce- 

 ment pipe, the bids on it were low-er than for the clay pipe. The 

 contract w^as awarded to the lowest bidder, who proposed to furnish 

 pipe made on a Thomas-Hammond pipe machine. The machine was 

 brought to Glendale from Los Angeles in October and was engaged 

 in pipe-making for about four months. The laying was completed 

 in May, 1918. Altogether the following list of pipe w^as delivered 

 laid in the trench : 



4,050 ft. of 14-inch pipe 

 25,425 " " 15- " 

 3,450 " " 18- " 



The great advantage of the use of cement pipe for irrigation con- 

 duits lies in the fact that the seepage and evaporation losses from 

 open ditches are prevented. These losses are appalling. Dr. Samuel 

 Fortier, Chief of Irrigation Investigations, U. S. Department of 

 Agriculture, states that "a large percentage of the water, estimated 

 at 40 percent of the amount taken in at the heads of the main canals, 

 is lost by absorption and percolation along the routes."* These 



•Bull. 126, U. S. Dept. Agr., 1914. p. 1. 



