Ptimping Stations. 155 



The ordinary speed is 2*29 revolutions a minnte, equal to a speed at 

 the periphery of 4 feet per second. The other four wheels are the 

 same diameter, 11 '81 feet wide, with scoops 6 feet 7 inches long, 

 and dip 4 feet below low-water. The speed is i'9i revolutions a 

 minute, equal to 3 feet a second The engines make 12 revolutions 

 to one of the wheel. The wheels work in a masonry raceway 

 rendered with cement. The clearance between the wheel and the 

 raceway is -f^ inch. The crest of the raceway is movable, and can 

 be adjusted to suit the height of the water in the canal. 



The eight wheels discharge at low-water of 0*30 metre, 2,922,708 

 cubic metres in twenty-four hours, equal to about 2000 tons per 

 minute. The consumption of coal for the year 1885 ^^ stated by 

 Baghos Nubar Bey, in a paper in ' Trans.' Instit. C.E., to be 3 • 10 lb. 

 per water horse-power per hour. 



These wheels differ from those constructed in this country in having 

 the scoops placed much closer together, their great width, and slow 

 speed. The results attained appear to be very satisfactory, the con- 

 sumption of coal as given being small as compared with that of the 

 Dutch or English wheels. 



Katatbeh. — The machinery originally erected for raising the water 

 at this station was put up by Messrs. Easton and Co. in 1882. It 

 consisted of a set of ten Archimedean screw pumps, placed parallel 

 with each other, and worked by a shaft 164 feet long, coupled to 

 three steam engines. These screw pumps were 39 feet long by 

 10 feet diameter, the cores being 4 feet diameter. The casing, core, 

 and spiral strut were of wrought-iron plates. The spiral had a pitch 

 of 25 feet. The screws made from 5 to 6 revolutions a minute, and 

 discharged 25 cubic metres per revolution (about 136 tons per 

 minute). These screws were found unequal to the enormous weight 

 of water, and the cores broke at about one-third of their height. 

 Seven of these were subsequently removed, the remaining three being 

 kept as a reserve after being strengthened by tension rods placed 

 radially, so as to connect the core and the casing. The weight was 

 relieved by a ring of rollers fixed at two-thirds of the height, which 

 turned on a roller path fastened to the masonry. The screws were 

 replaced in 1883 by five vertical-action centrifugal pumps constructed 

 by Messrs. Farcot and Co., each driven by a separate engine. The 

 new engines are placed on the foundations prepared for the sluices 

 of the screws, and the pumps in the basin below. The vertical 

 shaft of the pumps has a crank to which the rod of the engine is 



