EUEAL ENGINEERING. 585 



ground was barely moist while other series were apparently only slightly damp, 

 even where the drain was filled with mud and water. Of the handmade tile 

 and under the worst conditions series 2 [of 1 : 2J mixture] was, with very few 

 exceptions, found to be slightly damp, as indicated by the appearance of the 

 fractured surfaces. . . . The richest mixtures used were nearly always found 

 partially or completely saturated. . . . The tile of series 14 [of 1 : 3 mixture], 

 next to those of series 2, showed the smallest amount of absorption, while the 

 tar-coated tile of series 5 [1 : 2 mixture] and the tile of series 6 [1: 2 mixture], 

 containing ferrous sulphate, were usually found to show the greatest absorp- 

 tion. . . . The absorption of the machine-made tile varied as the amount of 

 cement contained in them. The tile of series 9 and 10 [1 : 1^ mixture] were 

 usually found apparently dry or only partially saturated with a few wet spots 

 in the fractured surfaces while the tile of the leanest mixtures were always 

 found saturated." 



It is concluded that special care should be observed to employ only the best 

 materials and good workmanship in fabrication of drain tile. If these pre- 

 cautions are not observed failure will result if the drain is locate<l in some of 

 the more concentrated alkali soils similar to those found at Grand Junction, 

 Colo., and Garland, Wyo. 



" Drain tile manufactured ... of cement mixtures not leaner than 1 part 

 cement to 3 parts aggregate are apparently unaffected structurally when ex- 

 posed for one year in operating drains in very concentrated alkali soils. . . . 

 Drain tile made from cement mixtures leaner than 1 part cement to 3 parts 

 of aggregate should not be used in localities where the character of the alkali 

 and concentration are similar to that found at the site of the experimental 

 drain at Grand Junction, Colo. ; Montrose, Colo. ; and Garland, Wyo. . . . 

 Drain tile manufactured of 1 part cement to 4 parts of aggregate, the leanest 

 mixture used, is apparently unaffected structurally by exposure for one year 

 in an operationg drain in localities where the character of the alkali and the 

 concentration are similar to those found at Fort Shaw, Mont. ; Sunnyside, 

 Wash. ; Yuma, Ariz. ; and Roswell, N. Mex." 



Cost of drainage pumping' in southern Louisiana, C. W. Okey (Engin. 

 News, 7Jf (1915), No. 16, pp. 733-735).— Data, on the cost of operation of drain- 

 age pumping plants in southern Louisiana, secured in connection with inves- 

 tigations carried on since 1909 by the Office of Experiment Stations of the 

 U. S. Department of Agriculture, are reported, together with full information 

 on the kind and cost of fuel and labor and on the equipment of each station. 

 According to the tables, the cost varied with the conditions from 4.1 to 16 cts. 

 per acre-foot per foot of lift, the cost unit used. 



A previous report along similar lines in which the author is interested has 

 been noted from another source (E. S. R., 34, p. 283). 



Farm, drainag-e in North Carolina, H. M. Lynde (North Carolina Sta. Bui. 

 234 (1915), pp. 32, pi. 1, figs. 14). — This bulletin, prepared in cooperation with 

 the Drainage Investigations of the U. S. Department of Agriculture, emphasizes 

 the general need for better farm drainage in North Carolina, and deals in a 

 popular manner with the underlying principles and practice of the subject, 

 with particular reference to North Carolina conditions. " Farm drainage is one 

 of the most important agricultural operations with which the farmer in Noi-th 

 Carolina has to deal. Drainage lies at the basis of successful agriculture in the 

 Coastal Plain region, which comprises an area of over 14,000,000 acres, nearly 

 one-half the total area of the State. ... It has been estimated that from 

 five to six million acres of land now under cultivation in the State are in need 

 of better drainage." 



31501°— No. 6—16 7 



