. Mechanical appliances, mechanical movements and novelties of construction; a complete work and a continuation, as a second volume, of the author's book entitled "Mechanical movements, powers and devices" ... including an explanatory chapter on the leading conceptions of perpetual motion existing during the past three centuries. MEASUREMENT OF POWER, SPRINGS. 3; 42. WIND FORCE REGISTER. The metal drum, ^ ^, is madeof tin plate ; it is two feet in height and one foot in diameter, suspended by a chain, b, to a strong support, r, onthe roof of the Observatory; its lowerend is connected by a chai
. Mechanical appliances, mechanical movements and novelties of construction; a complete work and a continuation, as a second volume, of the author's book entitled "Mechanical movements, powers and devices" ... including an explanatory chapter on the leading conceptions of perpetual motion existing during the past three centuries. MEASUREMENT OF POWER, SPRINGS. 3; 42. WIND FORCE REGISTER. The metal drum, ^ ^, is madeof tin plate ; it is two feet in height and one foot in diameter, suspended by a chain, b, to a strong support, r, onthe roof of the Observatory; its lowerend is connected by a chain and guiderod, d, with a spiral spring at the bot-tom of the case. On the top of thisspring is a pencil; it bears against thesheet of paper, g g, fastened to a boarddrawn aside by a clock. When thewind blows, the tin cylinder is forcedinto some other position, as is shown inthe dotted figure, a a, and the pencil isdrawn upward. The more violent thewind the further will the tin cylinder bepushed aside, and the higher the pencildrawn. The force necessary to drawthe pencil upward to a given point isdetermined by direct experiment, and ex-pressed in pounds weight upon a squarefoot. The direction from which the windblows makes no difference, as it alwayshas the same surface to press 43. RECORDING WIND METER. On the ends of a crosssupported by a vertical shaft several feet above the roof of the building, are four hemispherical copper , whatever may be the directionof the wind, are caused to turn roundwith a speed, as has been determinedby experiment, of about one-third thevelocity of the wind. To the lower end of the shaft thusmade to revolve by the cups is attachedan endless screw connecting with a trainof wheels, which move a cam. Thewheels are so arranged that one turnof the eam answers to 15 miles in themovement of the wind. A pencilwhich rests on the edge of the cam,
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Keywords: ., bookauthorhiscoxgardnerdexter18, bookcentury1900, bookdecade1910
