2020 EXPERIMENT STATION RECORD. 



"The quantity of water discharged by the drains is lowest during the active 

 period of vegetation from April to September," due apparently to the transpiration 

 by plants, and does not closely follow increased rainfall. The average monthly dis- 

 charges for ten years are platted with the rainfall, temperature, and evaporation, 

 showing that the drainage increases as temperature and evaporation decrease, the 

 maxima occurring in December and March. But annual means of these quantities 

 platted for a 10-year period show similar curves throughout. 



The work rests on the supposition of an impervious subsoil, evaporation being 

 taken as the difference between rainfall and the combined loss by drainage and 

 transpiration, the latter being obtained by weighing the dry matter produced and 

 multiplying by empirical constants as determined by M. Risler. 



Sedimentation: Its relation to drainage, J. W. Dappert (Engin. News, 55 

 I 1906), No. 5, pp. 125, 126). — An abstract of a paper presented before the Illinois 

 Society of Engineers and Surveyors in January, 1906. 



From his experience with over a hundred drainage districts the author has found 

 that open drains are invariably subject to filling up with sediment, from the wash of 

 high-land streams, or from the sloughing and caving of banks, regardless of the 

 grades employed. He recommends as preventives that ditches be dug wider and 

 deeper than required, to allow for sloughing of the slopes; that tile-drains should be 

 given several feet outfall into the ditch; that curves be avoided, and waste banks be 

 put well back from the edge of the ditch; that concrete walls be used at tile outlets 

 and where surface water enters, and that willows and other water-loving trees should 

 be cut out. Regular inspection and repairs are indispensable. 



In conclusion he adds: "With all these things done, and even well done, the open 

 ditches will yet require frequent recleaning, but their period of efficiency can be 

 greatly extended by their proper care and management. Lastly, I reiterate, do not 

 build an open ditch where a tile-drain, pipe, or conduit can possibly be employed." 



Proceedings of the Second Annual Iowa State Drainage Convention {Ames: 

 Iowa Drainage Assoc, 1905, pp. 65, figs. 7).— This report includes a paper by C. G. 

 Elliott on drainage assessments, damages, and taxes, and the relation of drainage 

 projects to roads and railroads; an address by R. M. Wright on the new Iowa drain- 

 age law, with particular reference to the constitutionality of the exercise of eminent 

 domain by drainage systems; a paper by A. Marston on road drainage, describing the 

 work of the State highway commission; an address by D. A. Kent on tile drainage, 

 especially for corn lands; an article by L. E. Ashbaugh on the reclamation of mean- 

 dered lake beds by drainage; and a paper on the relation of soil to underdrainage, 

 by W. H. Stevenson. 



Third report on the highways of Maryland, A. X. Johnson ( Md. Geol. Survey 

 [Rpf], 5 {1905), pp. 145-218, pis. 4, figs. 4). — This report includes a progress report 

 of work done by the counties under the direction of the State geological survey, cost 

 data for road building in different localities, an account of laboratory tests of road 

 materials, and a set of standard specifications for earth, macadam, and telford roads. 



A new method for tensile tests of cement is used, in which the cement is molded 

 in the form of a ring, which is broken by hydraulic pressure applied by expanding 

 a rubber tube inside the ring, in a machine of special design. An outline of a sug- 

 gested county-road law is given, providing for three elected county road commission- 

 ers and a county road engineer with a permanent staff of supervisors. 



Building the new barn, A. P. Ketchen {Rpt. Farmers' Insts. Ontario, 10 {1904), 

 pt. I, pp. 82-95, figs. 8). — The author considers in a popular manner the approved 

 methods of building foundations, basement walls, doors, windows, and floors for a 

 large barn. The question of ventilation is fully discussed. 



Machinery in agriculture, Stange {Vrtljschr. Bayer. Landw. Rat., 10 {1905), 

 No. ;, pp. 599-603). — A review of a work by Dr. Alex. Lang (Berlin: Geo. Siemens, 

 1904). 



