588 EXPERIMENT STATION RECORD. [Vol.43 



the U. S. Reclamation Service, discusses the scientific and practical aspects 

 of irrigation water utilization in connection with the presentation of data on 

 the use of water for the seven seasons from 1012 to 1918, inclusive, by 22 

 irrigation projects. 



The soil, climate, and class of crops are considered to be the three funda- 

 mental factors upon which the probable water requirements must be based in 

 the design of irrigation systems. It is pointed out that alfalfa is the backbone 

 of irrigation agriculture. Combining all the projects, the percentage of area 

 devoted to forage crops, mostly alfalfa, is 50, indicating that other crops are of 

 more or less incidental importance from a broad viewpoint. Furthermore, the 

 data show that for purposes of design of the principal canals and structures 

 and determination of storage requirements, a knowledge of the quantity of. 

 water required each month is of prime importance. 



Data on seepage losses from canals indicate that concrete lining is the most 

 practicable and satisfactory. " It is very costly, especially the lining of old 

 canals which have a greater cross section than is needed for the smoother 

 concrete surface, but its results are certain and permanent, especially in the 

 milder climates, and for this reason lining with concrete is now recognized as 

 the standard method of preventing seepage losses. Even concrete lining, how- 

 ever, does not prevent losses entirely." It is concluded that 25 per cent is 

 about the minimum loss that can be safely assumed under favorable conditions, 

 and that 50 per cent is sufficiently high under unfavorable conditions. 



Use of water from Kings River, Calif., 1918, H. Barnes (Calif. Dept. 

 Engin. Bui. 7 {1920), pp. 119, pis. 13, figs. 2). — This report presents the results 

 of a field study of the use of water for irrigation from Kings River during 1918, 

 conducted under a cooperative agreement between the Bureau of Public Roads 

 of the U. S. Department of Agriculture and the California State Department of 

 Engineering. In addition, methods of water delivery, organization of compa- 

 nies for water distribution, and essential conditions affecting the use of water, 

 including water contracts, water rates, and the physical characteristics of the 

 various systems are dealt with. 



The data show a total of 40 diversions with a capacity of practically 10,450 

 second ft. The area served is 840,000 acres, of which 553,000 acres are esti- 

 mated to be irrigated. 



Of the organizations diverting water, 15 are upon a cooperative basis and 6 

 sell or have sold contract water rights. The cost of water from contract 

 companies varies from 60 cts. to $1 per acre per year and from the cooperative 

 oi'ganizations from 10 cts. to $1 per acre. It is noted that the average gross 

 duty of water represented by diversions to the capacity of 10,450 second ft. 

 upon the total 840,000 acres under ditch is in the ratio of 1 second ft. to 80.4 

 acres. 



The two most prominent features of the situation on Kings River are said 

 to be the need for public supervision of diversions on tlie basis of a clearly 

 defined list of priorities, and a more systematic and more economical admin- 

 istration of the distribution of water to irrigators. 



Comparative study of the potable waters of the canton of Ticino from 

 the chemical and microbiological viewpoints, A. Vekda {Helvetica Chim. 

 Acta, 3 {1920), No. 1, pp. 3-22). — Considerable data on the geology and the 

 chemical and biological composition of the potable waters of the canton of 

 Ticino in Switzerland are given. 



Regarding chemical composition, it is noted that the waters in general have 

 a low mineral content and are relatively poor in lime. A common characteris- 

 tic of the majority of these waters is tlie absence of nitrates and the presence 

 of ammonia in water which ts relatively impure. As a whole, the waters are 



