Page:Lowell Hydraulic Experiments, 4th edition.djvu/81

61 EXPERIMENTS ON THE POWER OF A CENTRE-VENT WATER-WHEEL AT THE BOOT COTTON-MILLS IN LOWELL, MASSACHUSETTS.

110. wheel is one of a pair constructed from the designs of the author by the Lowell Machine Shop, for the Boott Cotton-Mills, in 1849. During a considerable portion of the year, the fall, on which these wheels operate, is about nineteen feet; with this fall, and with the regulating gates raised to the full height, they each furnish an effective power of about 230 horse-power.

A patent for the term of fourteen years was issued, July 26, 1838, by the Government of the United States of America, to Samuel B. Howd, of Geneva, in the State of New York, for a water-wheel resembling, in some respects, the wheels at the Boott Cotton-Mills. Under this patent, a large number of wheels have been constructed, and a great many of them are now running in different parts of the country; they are known in some places as the Howd wheel, in others as the United States wheel; they have uniformly been constructed in a very simple and cheap manner, in order to meet the demands of a numerous class of millers and manufacturers, who must have cheap wheels if they have any.

111. Figures 3 and 4, plate IX, are a plan and vertical section of one of the Howd wheels, constructed by the owners of the patent right for a portion of New England. $$A$$, the wooden guides by which the water is directed on to the buckets; $$B$$, buckets of cast-iron, fastened to the upper and lower crowns of the wheel, by bolts; the upper crown is connected with the vertical shaft $$E$$, by the arms $$C.\ \ D$$, the regulating gate, placed outside of the guides; this is made of wood; the apparatus by which it is moved is not represented; it is a simple arrangement of levers. The upright shaft $$E$$ runs on a step at the bottom. This wheel is usually placed in the bottom of a rectangular forebay, which, in high falls, may be closed at the top, so as to avoid the necessity of using a vertical shaft of great length. The peculiarly shaped projections on one side of the buckets, it is said, increase the efficiency of the wheel, by diminishing the