86 EXPERIMENT STATION EECORD. 



Hydrostatic catenary flume on a concrete aqueduct, H. B. Muckleston 

 (Enrjin. News, 77/ (1915), No. 2, pp. 58-63. pgs. 9).— The details of the design 

 and construction of a reinforced concrete viaduct nearly 2 miles long, carrying 

 a trough flume in the shape of a hydrostatic catenary, are given. This structure 

 is part of a Canadian irrigation scheme and carries on hydraulic gradient a 

 maximum flow of 900 second-feet. 



Cost of electric pumping for irrigation {Elect. World, 66 {1915), No. 2, pp. 

 68-71, figs. 9). — Results extending over six years, obtained on the south side 

 unit of the Minidolva project of the U. S. Reclamation Service, are reported. 



Water is raised by large pumping stations up three 30-ft. steps. At each level 

 some water is taken out for the lands that can be covered. The power required 

 is the same as though all the water were lifted to an average of from 66 to 69 ft. 

 Electricity is supplied from a power plant utilizing a 46-ft. fall in the Snake 

 River at INIinidoka Dam. Energj' is transmitted about eleven miles from the 

 power house to the pumping stations over 33.000-volt transmission lines, and 

 supplied to the pumping station at cost. The unit of cost for operation, main- 

 tenance, and depreciation has been taken as the acre-foot lifted 1 ft. high or the 

 so-called " foot-acre-foot." Beginning with the year 1909 and including the year 

 1914 the total annual cost for operation, maintenance, and depreciation per foot- 

 acre-foot for the six years in succession was !?0.00626, $0.00473. .S0.(X)38."). .'?0.00491. 

 .$0.00?,71. iin<l .^fK'M).'?!?. 



Why drainage of irrigated lands is necessary and how the problem is 

 handled, D. W. IMrRi-iiY {Enrjin. Rec, 72 {1915), No. 2. pp. 36-38, figs. 2).— 

 It is pointed out in this article that leakage from canals and extensive use of 

 water for crops cause saturation of the subsoil and the deposition of alkali on 

 the ground surface. The fundamental purpose of drainage works is considered 

 to be to control the ground-water table and prevent its rising high enough to 

 impair the irrigability of the .soil, either through .saturation or through the 

 accumulation of alkali. " Drainage works must be .'jo located and constructed 

 that they will be effoctive in skimming off or disposing of the top portion of the 

 ground waters over those areas whore there is a tendency for them to reach the 

 surface." The determination of location, type, and depth of drains to be used 

 is said to depend on local conditions in each particular case, and can be de- 

 termined only after careful investigations and study of the character of the sub- 

 soils and the ground-water movement through thorn. 



Superelevation of curves on highways, Illinois practice, H. E. Bilgeb 

 {Engin. News, 7^ {1915), No. 2. pp. 74, 75).— Where brick and concrete roads 

 are used almost exclusively it is stated that. " all matters considered, the most 

 satisfactory treatment of these types on curves is to carry the profile of the 

 center line and of the inner edge of the pavement around the cun-e without a 

 break, but to elevate the outer longitudinal half of the slab 2 in. for the 10-ft. 

 pavements and 4 in. for the 18-ft. ones. On the inner as well as the outer longi- 

 tudinal half of the slab the convexity of the surface ."Should be avoide<l, to the end 

 that the entire portion of the slab that comes upon the curve may be a surface 

 having a straight-line top on any cross section. Gravel and macadam road sur- 

 faces should be similarly treated on curves ... by elevating the outer longi- 

 tudinal half of the metaled way by an amount equal to twice the crown on 

 tangents for the particular tyi^e in question." 



Limestone road materials of Wisconsin, W. O. Hotchkiss and E. Steidt- 

 MANN {Wis. Geol. and Nat. Hist. Surveu Bui. 34 {191^). Eeon. Ser. 16, pp. 

 Til I +137, pis. 4i, figs. 2). — This report deals with the origin, extent, distribu- 

 tion, and general characteristics of Wisconsin road materials, and gives a de- 

 scription of these by counties. 



