AGRICULTURAL ENGINEERINO. 289 



" n=.0300 for canals in earth in ratlier bad condition having the bed partially cov- 

 ered with debriij; or having comparatively smooth sides and bottom with 

 bunches of grass and weeds projecting into tlie water antl more or less aquatic 

 plants growing in the channel. 

 "n = . 0350 for small ditches having a small uneven bed and for canals in earth m 



fairly good condition but partially filled with aquatic plants. 

 " n=.040 for canals inearth whose channels are about half full of a(juatic vegetation. 

 "n = .0."iOfor canals in earth Avhose channels are al)out two-thirds full of aijuatic 

 vegetation." 



Practical irrigation, C. T. Johxston and J. D. Staxxard ( U. S. Dept. Agr. Year- 

 book 190(1, pp. 491-.il;2,tig><- 9). — This article explains methods of laying out and con- 

 structing small ditches with varying grades and cross sections, the laying out of field 

 laterals, methods of applying water to crops, when to irrigate, and cost of building 

 and maintaining a ditch. 



A study of the practice of irrigation on the plain of Urgel, Spain, P. 

 PniLiPPAR i^Ann. Agron., 27 {1901), No. 5, pp. 220-237, Jig. i).— This article describes 

 quite fully the system of water management and methods of irrigation practiced in 

 this region, and discusses the results obtained. 



The Chapman subirrigation plant {('((fij'ornia Cuff., 16 {1901), Xo. 20, p. 305, 

 tig. i).— A brief description. 



Tenth Biennial Report of the State Engineer to the Governor of Colorado, 

 1899 and 1900 {Cufonido Sfafe Eng. Rpt. 1S99 and 1900, pji. 396, pfs. ii).— This is 

 an account of operations during the 2 years ended November 30, 1900, and includes 

 a list of the irrigation officers with recommendations regarding the improvement of 

 the irrigation system of the State; reports on the internal improvements made; an 

 abstract of supreme court decisions relating to irrigation; reports of superintendents 

 of irrigation and water commissioners; ditch and reservoir filings; seepage measure- 

 ments and ditch ratings; and gagings of streams with comparative tables of discharge. 



.Agricultural machinery at the Paris Exposition of 1900, U. Coupan {Buf. 

 Soc. Agr. France, n. ser., 32 {1900), Dec. 15, pp. 469-479, figs. 5; 33 {1901), Jan. 1, 

 pp. 43-49, figs. 4; Jan. 15, pp. 97-106, figs. 11; Feb. 1, pp. 165-176, figs. 5; Feb. 15, 

 pp. 280-286, figs. 4; Mar. 1, pp. 362-370, figs. 5). — Brief notes are given on plows, 

 cultivators, scarifiers, pulverizers, rollers, harrows, mechanical diggers, fertilizer dis- 

 tributers, seed drills and planters, hoes, pumps, hydraulic rams and other water 

 lifts, agricultural artillery, harvesting machines of all kinds, threshing machines, 

 and presses, mills, and other machines for preparing crops for handling and use. 



Results of tests of alcohol motors in Germany, E. Leplae {Les resultats des 

 ess'iis di' iiiofcnrs a afconf ck Affemagiie. Brrchf : L. Jh'afckmans, 1901, pp. 17). 



The selection of materials for macadam roads, L. W. Page ( U. S. Dept. Agr. 

 Yearfjook' 1000, pp. 349-356). — This article discu.'^ses the importance of the phy.sical 

 properties of rock in road building and of a record of traffic for proposed roads and 

 methods of measuring traffic, the ada])tation of material to different kinds of traffic, 

 and metho<ls of determining the value of rocks for road building. Attention is called 

 to the establishment of a road material laboratory in the Division of Chemistry of this 

 ])ei)artnient and the plan and purpose of the w'ork to be undertaken is explained. 



Mountain roads, J. "\V. Abbott ( U. S. Dept. Agr. Yearfmok 1900, pp. 183-198, pfs. 

 3). — The construction and maintenance of such roads are discussed in a popular 

 manner. 



Construction and care of earth roads, I. O. Baker {Iffinois Sfa. Bid. 65, pp. 

 73-93, fig. ;).— This bulletin is "addres.sed to the farmers chiefly," and deals with 

 the subject under three main heads — construction, maintenance, and administration. 



Good dirt roads for Mississippi, J. W. Fox and W. L. Httchixsox ( .l//.wks//);;^ 

 Sta. Bui. 67, pp. 16, figs. t;). — The road laws of Mississippi are l)riefly summarized 

 and the system of road maintenance of the State is discussed. Methods of building 

 and maintaining dirt roads are briefly exjjlained. 



