588 EXPERIMENT STATION RECORD. 



parallel vvltli tlie stream flow, and also to show the effect of cross-currents at 

 angles with the stream flow, are given. 



A comparative rating curve of the two meters shows that both give practically 

 a straight line, but the results from the screw type are slightly more consistent. 

 When turned at angles varying from to 90° by Increments of 10° with the 

 stream flow, the revolutions of the screw meter were decreased almost propor- 

 tionately to the number of degrees turned, while the revolutions of the cup 

 meter were increased when turned with its head to the left and decreased when 

 turned to the right. Both meters followed their regular rating curves in all 

 ordinary depths, but when brought nearer the surface than 1 ft., measuring from 

 the center of the wheel, the revolutions of both were decreased, and when 

 brought nearer the bottom than 6 in. the revolutions of the cup meter were 

 decreased and those of the screw meter increased. 



The revolutions of the cup meter were increased if the open part of the cups 

 was near the side of the tank as the meter advanced, but were decreased if 

 the point of the cups was near the side. The side swaying of the rating car 

 decreased the revolutions of the screw meter and increased those of the cup 

 meter. Rating the screw meter bacliwards decreased its revolutions. When the 

 meters were only partially covered, as in very shallow water, the curves were 

 very eccentric. Curves for the cup meter were the same whether or not the tail 

 was attached. 



See also a previous note by Scobey (E. S. R., 31, p. 288). 



Methods of finding center cut for economic locations of banked irrigation 

 ditches, F. C. Snow (Etigin. and Contract., J,l (1914), No. 16, pp. 481, 482, figs. 

 S). — Formulas and methods for computing diagrams for determining the center 

 are given, with a sample diagram. 



Centrifugal pumps for irrigation, C. F. Bbaun {West. Engin., 3 {1913), No. 

 S, pp. 124-138, figs. 14)- — It is the purpose of this article "to point out a few 

 features, which, if carefully regarded, make the centrifugal pump a highly 

 efficient, very reliable unit, capable of delivering water at surprisingly low cost, 

 and of competing with gravity canal systems." 



The author deals with the design of both turbine and volute pumps, discuss- 

 ing multi-stage pumps, centrifugal pump limitations, multi-impeller pumps, me- 

 chanical details, clearance bushing rings, hydraulic-balance, thrust-bearing, 

 materials of construction, pump characteristics, methods of drive and installa- 

 tion, and cost. 



Irrigation, J. L. Couxteb and R. P. Teele (Thirteenth Census U. S., 5 (1910), 

 pp. 827-876, pi. 1, figs. 15). — This is a more extensive report of work previously 

 noted (E. S. R., 28, p. 888). 



Irrigation pumping in Nevada, C. A. Nobceoss (Nev. Bur. Indu.<i., Agr., and 

 Irrig. Bui. 8 (1913), pp. 78, figs. 35). — It is the purpose of this bulletin to show 

 the practical outlook for irrigation pumping in Nevada within lifts of 50 ft. 

 In dealing with the underground water supply the general principles governing 

 surface and artesian water are discussed from the standpoint of pumping. 

 Methods of computation of the cost of pumping water are described, and tables 

 are given of the cost per irrigated acre with different kinds of power and at 

 pumping lifts up to 50 ft. In dealing with pumping efficiency and types of 

 pumps the several kinds of pumps adapted to low-lift irrigation pumping are 

 discussed. A final section dealing with wells, pits, and reservoir construction 

 gives practical information in relation thereto, Including the cost of drilling 

 artesian wells. 



Irrigation, C. H. Pead (Pruc. Rhodesia Sci. Assoc, 12 (1913), pt. 3, pp. 152- 

 161). — The author attempts to point out the economic possibilities of irrigation 

 in Rhodesia. 



