Pumping Stations, 1 5 3 



this form is advantageous in entering the water, is not well adapted 

 for parting with it. The wheels are 20-66 feet in diameter by 

 3-70 feet wide, and have sixteen curved iron scoops. The wheel 

 makes 5^ revolutions a minute to sixty of the engine, the speed at 

 the periphery being 5-66 feet per second. The dip is about 4 feet, 

 and the lift from 2-60 feet to 4*25 feet, the mean being 3*60 ; each 

 wheel can discharge 105 tons a minute. The wheels are driven by 

 two single-cylinder condensing horizontal engines of 30 actual horse- 

 power. The cylinders are 1*37 feet in diameter, with 2*16 feet 

 stroke. Steam is generated in two double-flued Lancashire boilers, 

 each 6*87 feet by 28 feet long, having twelve Galloway tubes. The 

 safety valve is weighted to blow off at 90 lb» The machinery was 

 erected by the Prins Van Orange Company m 1875. The wheels 

 work on an average 120 days of fifteen hours in the year. 



One boiler is sufficient to generate steam for the cwo engines when 

 discharging 210 cubic metres per minute. With the boiler first 

 supplied, the consumption of coal was at the rate of 1 2 • 7 6 lb. per 

 water horse-power. The ground in this polder is principally moor, 

 and the water contains a great deal of sulphur and saltpetre, which 

 had a very bad effect on the boilers, which were worked out in eight 

 years. With the new boilers working at a pressure of 90 lb., the coal 

 consumption has been reduced from about 4 to aj tons per day of 

 fifteen hours. The average consumption now is at the rate of 

 7*15 lb. per horse-power of water lifted. 



MiNDEN, Holland. — The illustration given in Plate 7 is an ex- 

 ample of a centrifugal pump for the drainage of land, driven directly 

 by a vertical engine. The pump was made and sent to Holland by 

 Mr. Hett, of Brigg, and is 36 inches in diameter, with pipes 10 inches 

 in diameter. The speed of the engine is about 1 20 revolutions a minute* 

 It is calculated to discharge 1700 gallons (7^ tons) a minute to a 

 height of 6 feet. All the working parts are of forged steel, including the 

 crank, which is counterbalanced and cut out of the solid. Full 

 lubricating arrangements are provided, so that the engine can run for 

 almost any length of time without stopping. The engine has a shifting 

 eccentric for varying the cut-off. The cost of the pump, engine, and 

 pipes was 250/. The engine and pump was erected and the boiler 

 supplied by the Machinefabriek at Breda, and is reported by the 

 proprietors as keeping their land dry in a very satisfactory manner. 



Katatbeh and Atfeh, in Egypt.— These pumping stations 

 were formed for lifting the water from the Nile for irrigating the 



