1120 EXPERIMENT STATION RECORD. 



Agriculture in the valley of the Ahr, H. Dcpays and L. Lebrun (Jour. Agr. 

 Prat., n. ser., 11 {1906), No. 8, pp. 241-24$, figs. 5).— This article describes briefly 

 irrigation practice in the valley of the Ahr. The irrigation works are simple. The 

 ditches are usually made with rectangular cross section in order that they may take 

 up no more room than is necessary. Water is carried in rectangular flumes made of 

 galvanized iron supported on I-beams. The water is used on meadows, the charges 

 for water being 20 marks per hectare per year. 



Pumping- machinery at Mildura (Impl. and Mach. Rev., 31 (1906), No. 372, 

 p. 1406). — At Mildura, Victoria, water is pumped for 8,000 acres of land. The water 

 is raised at three separate lifts, 20, 25, and 25 ft. Water is pumped at the rate of 

 26,000 gal. per minute. As a rule there are five irrigations during the year, each 

 lasting 28 days, and the pumps are run at a cost of $300 per day, or about $42,000 

 per year. The fuel is wood. The costs are met by a water tax which varies from 

 30 to 40 shillings per acre for the land covered. The land receives an average depth 

 of about 22 in. per annum. 



A Hawaiian pumping plant for irrigation (Engin. Rec, 53 (1906), No. 10, 

 p. 350). — A description of a plant utilizing a small mountain stream by means of 

 impulse wheels and an electric power plant. A method for regulating the speed of 

 the dynamo, motor, and pump has been adopted so that the efficiency is not impaired 

 when the supply in the hills is short, Larger impulse wheels are then used, giving 

 a slower speed to the generator. With an automatic device to keep the field con- 

 stant the voltage and cycles are diminished in proportion, the motor then falling off 

 in speed without decreased efficiency. 



Canals and ditches, M. Ringelmann (Jour. Agr. Prat., n. ser., 11 (1906), No. 7, 

 pp. 210-212, figs. 8). — This article summarizes foreign and American measurements 

 of percolation of water from ditches, and discusses methods of prevention of losses 

 in canals used for carrying water. It describes methods of preventing seepage losses, 

 including concrete lining, masonry lining of ditches w T ith rectangular cross sections, 

 and the use of flumes. 



The Belle Fourche dam, Belle Fourche project, South Dakota, R. F. Wal- 

 ter (Engirt. Rec, 53 (1906), No. 9, pp. 307-310, figs. 7).— This dam is one of the largest 

 earth dams in the United States, being over a mile in length and containing 1,600,000 

 cu. yds. The details of the wasteway, conduits, and gates are described in detail. 

 An unusual feature is the proposed concrete-block facing laid over gravel in lieu of 

 riprap. 



The Belle Fourche irrigation works, South Dakota, W. W. Patch (Engin. 

 News, 55 (1906), No. 8, pp. 210-212, figs. 5). — A brief account of the project, with a 

 description of the more important structures used. 



The drainage of earth roads (Engin. Rec, 53 (1906), No. 18, pp. 564-566). — 

 This is an abstract of a bulletin on this subject by Prof. Ira 0. Baker, published by 

 the University of Illinois. 



It is recommended that tile drains be laid at the side of the road at a depth of 3 

 or 4 ft., such a drain on one side of an ordinary country road being held to be suffi- 

 cient. The drain might be more effective in the middle of the road, but the expense 

 of putting it in would be so much greater that a drain at the side of the road is pre- 

 ferred. There is no limit to the steepness of the grades on which tile drains may 

 be used, but the grade should not be less than 2 in. per 100 ft. It is important that 

 the tile drains should have a free outlet. The cost of putting in 5-in. tile drains is 

 given as $200 to $250 per mile. 



Side ditches are necessary whether the tile is used or not. These should be broad 

 rather than deep, with easy slope toward the road in order that vehicles may not be 

 harmed if they get into these ditches. Water should not be carried long distances in 

 these side ditches, but outlets should be provided at short intervals. Roads should 

 be crowned sufficiently to provide for rapid surface drainage into the side ditches. 



