1016] ET7BAL ENGINEEEING. 185 



comprehensive use of machinery of various types ; the arrangement and group- 

 ing of farm buildings and structures, as well as the construction of individual 

 buildings ; and the development of natural resources for furnishing power, as a 

 substitute for manual and animal labor now employed at considerable incon- 

 venience and excessive overhead cost." 



The law of irrigation, compiled by C. F. Davis (Fort Collins, Colo.: [Com- 

 piler'\, 1015, pp. 346). — This text, comprising 2G lectures, is intended for the 

 secondary schools in the West in which a course in the law of irrigation is given. 

 The lectures aim to give a working knowledge of the law which controls the 

 large number of questions that have arisen from the appropriation and use of 

 water in the western United States and also deal with the history of irrigation 

 and Irrigation enterprises in other lands. While the lectures are based pri- 

 marily upon the law in Colorado, they also point out wherein this law diifers 

 from the laws in other States. 



Irrigation practice and eng'ineering. — III, Irrigation structures and dis- 

 tribution system, B. A. Etcheverky (New York and London: McGi'aw-Uill 

 Book Co., 1916, vol. 3, pp. XV +438, pis. 35, figs. iS6).— This, the third volume 

 of this work (E. S. R., 34, p. 482), is devoted to that part of irrigation engineer- 

 ing related to irrigation structures and distribution systems. It deals with the 

 following subjects : 



Diversion works ; diversion weirs ; design of diversion weirs ; design of 

 diversion weirs of the loose rock-fill Indian type ; dynamic forces produced by 

 flow of water over weii-s and their effect on the design of weirs ; description of 

 diversion weirs ; scouring sluices, fish ladders, logways ; main head gates or 

 regulator for canal system ; gate-lifting devices ; canal spillways, escapes, and 

 wasteways ; sand gates— sand boxes ; crossings with drainage channels ; drops 

 and chutes in canals ; distribution system ; check gates ; lateral head gates and 

 delivery gates ; road and railroad crossings with canals, culverts, inverted 

 siphons, and bridges ; special types of distribution systems — wooden flume, 

 wooden pipe, and cement pipe distribution systems ; and measuring devices. 



The flow of water in irrigation channels, G. H. Ellis (Proc. Amer. Soc. 

 Civ. Engin., 42 {1916), No. 2, pp. 181-204, Pls. 2, figs. 4).— This paper presents 

 a study of experimental data previously reported by Scobey (E. S. R., 33, p. 183), 

 the result of which was to deduce an experimental formula V=C -R"** /S°* for 

 the flow of water in channels in which the coeflicient C varies from about 40 to 

 140, depending on the roughness of the channel. " For general conditions the 

 following formulas are submitted : For concrete channels, "F^^IOS R"-^^ S°' ; for 

 wooden channels, y=:100 22°°' S*'; for earth canals, Y=QQ R""^ S"*." Inci- 

 dentally the need of care in the selection of a value for the coeflicient of rough- 

 ness is brought out. 



The automatic volumeter, E. G. Hopson {Proc. Amer. Soc. Civ. Engin., 41 

 {1915), No. 8, pp. 1891-1908, figs. 9). — "This paper describes an apparatus in- 

 tended to gage the flow of fluids by the collection of a proportionate part of 

 the flow, or its equivalent, in a small vessel where it can be readily measured 

 at any time. This result is accomplished by the use of very small orifices for 

 the purpose of regulating the discharge into or out of the collecting vessel, and 

 other special arrangements whereby the pressure head under which the dis- 

 charge into the collecting vessel takes place is at all times the equivalent, or 

 a constant ratio, of the velocity head of the liquid or gas being measured. . . . 



•' The practical operation of the device should probably be first for irrigation 

 uses, and particularly for measurements of individual service flows or flows in 

 small laterals. . . . 



"The device, as applied to irrigation use, has the advantage that it is inde- 

 pendent of such matters as drifting sand, weeds, or any floating or suspended 



