190 PRACTICAL DRAINAGE 



average. If the land is. so wet as to require cribbing of 

 the trench the cost may run up to $50 an acre or even 

 higher. He says that the price of tile may be figured at 

 about i cent per inch of inside diameter for each foot of 

 length for small sizes and about 2 cents for large sizes. 

 Hand trenching costs from 15 to 25 cents a linear foot for 

 six feet deep. Machine trenching is considerably cheaper 

 but usually costs more than a dollar a rod. The system 

 installed at Kearney Park, California, with its pumping 

 system cost $59.59 an acre, but since it was to be used for 

 experimental purposes it was permissible that it be more 

 expensive than a system installed by the farmer for strictly 

 economic purposes. These figures must all be revised to 

 meet post-war prices. 



REFERENCES 



1. BATES, P. H., PHILLIPS, A. J., and WIG, R.J. Action of Salts in Alkali 



Water and Sea Water on Cements. U. S. Bur. Standards, Tech. 

 Paper, No. 12 (1912), 157 pp. 



2. BROWN, C. F. Farm Drainage. A Manual of Instruction. Utah 



Sta. Bui. 123 (1913), pp. 5-55- 



3. BROWN, C. F., and HART, R. A. The Reclamation of Seeped and 



Alkali Lands. Utah Sta. Bui. in (1910), pp. 75-91. 



4. BURKE, E., and PICKNEY, R. M. The Destruction of Hydraulic Cements 



by the Action of Alkali Salts. Mont. Sta. Bui. 81 (1910), pp. 41-131. 



5. HART, R. A. The Drainage of Irrigated Farms. U. S. D. A. Farmers' 



Bui. 805 (1917), 31 pp. 



6. HEADDEN, W. P. Destruction of Concrete by Alkali. Colo. Sta. 



Bui. 132 (1908), pp. 3-8. 



7. JEFFERY, J. A. Textbook of Land Drainage, 502 pp. (New York, 



1916.) 



8. KING., F. H. Irrigation and Drainage,' 502 pp. (New York, 1899.) 



9. MEADE, R. K. Experiments on the Action of Various Substances on 



Cement Mortars. Engin. Rec. 68 (1913), pp. 20-21. 



10. PARSONS, J. L. Land Drainage, 159 pp. (New York, 1915.) 



11. SIMS, C. E., and DIECKMAN, G. P. Investigation of the Effects of 



Alkali on Concrete Drain Tile near Lake Park, Iowa. Concrete- 

 Cement Age, 6 (1915), pp. 278-281. 



