BUBAL ENGINEEEING. 783 



canal, sand nnd waste gates to control the water wlilch is to be turned out and 

 wasted, branch canal lateral and delivery gates to regulate the water turned 

 out to branches of the system or to users, and bifurcation works and division 

 gates to regulate the flow of water In the main canal and that passing into 

 branches or laterals. 



The author does not attempt to treat the subject fully, but gives examples of 

 structures which are said to serve the purpose for which they ai'e intended 

 better than many others in common use. Since local conditions control many 

 features of gate structures the descriptions given relate to existing structures 

 In actual use which it is believed will prove suggestive and can be readily 

 adapted to other conditions by local engineers and ditch owners. 



The drainage of irrigated land, J. P. Marais {Agr. Jour. Union So. Africa, 

 7 (1914), No. 3, pp. 353-356).— The author briefly relates the results of his 

 experience in the drainage of irrigated land, particularly referring to methods 

 of removing injurious alkali salts. 



Drainage and reclamation of swamp and overflowed lands, C. Kettle- 

 BOBOUGH {Ind. Bur. Leg. Inform. Bill. 2 (1914), PP- 68). — It is the purpose of 

 this pamphlet to present briefly the evolution, progress, and present status of 

 drainage and drainage legislation in Indiana ; to enumerate and discuss the 

 most significant results achieved in other States; to point out the inadequacy 

 of the present system in the State, the magnitude and economic importance of 

 the question, and to suggest plans to bring the drainage laws of the State into 

 harmony with those of the other States and thus promote the rapid and perma- 

 nent reclamation of nonarable swamp lands. 



Drainage investigations on the northeast Missouri prairie, M. F. Miller, 

 C. B. Hutchison, T. R. Douglass, and R. R. Hudelson (Missouri 8ta. Bui. 

 118 (1914), PP- 44^-497, figs. 5). — Tile drainage experiments to determine the 

 actual economic gain in crop yields and to determine the relation of under- 

 drainage to fertilization are reported, together with a summary of data 

 secured from farmers who have had experience with tile drainage. 



It is concluded in general that for the wet sloughs and sags found in the 

 region the use of tile is a very paying proposition. " On the tight level prairie 

 where the water passes to the tile more slowly it is necessary to lay the tile 

 from 4 to 6 rods apart for satisfactory work, thus greatly increasing the cost. 

 , . . However, where the land is very level and where the tile are propei'ly 

 put in, the tiling of this land will pay. On the prairie land that drains well 

 naturally . . . while tiling may pay, this will depend upon the crops grown 

 and the particular character of the land in question. The return In such 

 cases is therefore doubtful." 



The fertilizer experiments indicated that when large supplies of available 

 fertilizers are added there is less need for tiling and the profit from it is 

 reduced. Drainage without any fertilizer treatment gave a total increase per 

 acre on all crops for six years after laying the tile of $26.55, or within $1.33 of 

 the cost of tiling. As an investment it seems profitable to apply manure and 

 rock phosphate on this soil, even more profitable to use bone meal and turn 

 under an occasional crop of cowpeas, while lime returns a good percentage on 

 the investment where the land is not drained. Upon tiling, the plant food in 

 the soil becomes more available and the detrimental effects of the acid are 

 removed, so that the only profitable soil treatment seems to be the use of a 

 legume green manure crop to supply nitrogen and organic matter which are 

 decidedly lacking." 



In addition to general suggestions as to the laying of tile it Is further con- 

 cluded not to be advisable to use a smaller size of tile than 4-in. In any case, 

 and In systems draining more than 30 acres an 8-in. main is usually more 



