Mr J. O. Stuart on the Turbine Water- Wheel. 159 



minute. The fall at my works, as measured for a turbine- 

 wheel, that is, from the surface of the water in the front lead 

 to the surface of the water in the tail-race, is 11 ft. 8^ in. I 

 have erected the turbine so as to take the full advantage of 

 this fall, and calculated it for venting this 6000 feet of water 

 per minute. 



The turbine consists of six principal parts, viz., 

 1 and 2, The wheel and shaft, 

 3 and 4, The sluice-cylinder and sluice, 

 5 and 6, The centre disc and pipe. 



These are all made of cast-iron, and the united weight is up- 

 wards of 7 tons. Besides these, there is the reservoir, or 

 wheel-house, as we may term it, which comes in place of the 

 arc of the ordinary water-wheel. 



I shall shortly describe each of these parts, and the de- 

 scription will be made more intelligible, as well as more in- 

 teresting, by reference to the drawing of a vertical section, 

 on the scale of one inch to a foot ; the drawing of a quadrant 

 of a horizontal section, full size, and the model of the whole 

 erection, on the scale of f th inch to a foot, — all which I now 

 exhibit. 



The reservoir is constructed of stone, solid ashlar, hewn 

 and jointed. It is eleven feet square within walls, and the 

 walls all round are two feet thick, the stones being alter- 

 nately headers and runners. At the depth of 11 ft. 8^ in., and 

 the supposed depth of tail-water from the front surface, two 

 beams of wood 12 in. square, crossing each other in the centre 

 of the square, are bedded in the causeway of the bottom, and 

 built into the side-walls, so as to aflPord a solid foundation 

 for the step, in which stands the upright shaft of the wheel. 

 4 ft. 6 in. above these beams, four beams 18 x 20 in. square, 

 cross the reservoir, placed so as to leave a square opening in 

 their centre 6 ft. 9 in. within ; and a flooring of 3 in. plank, caulk- 

 ed as a ship's deck, makes this opening (which it reduces to a 

 circular form) the only communication between the upper and 

 under parts of the reservoir. 2 ft. 6 in. from the surface of the 

 water in front, the one side of the reservoir stops, so as to allow 

 the ingress of the water, and the opposite side has an open 

 arch below the floor-beams, to permit the egress of the water. 



