Gareth and I share an affection for Kris De Decker’s Low-tech Magazine, which, per its masthead, “refuses to assume that every problem has a high-tech solution.” Like its content, its style stands in refreshing contrast to the frenetic pace of the modern blogosphere: Low-tech updates only once or twice a month, and those updates are lengthy, well-written, well-illustrated, and carefully researched.
They just put up a great article about the machines people used to lift and move heavy loads before the advent of steam power. Arguably the pinnacle of human-powered lifting technology were Sir William Fairbairn’s hand-cranked “Tubular Cranes,” one of which is shown above as illustrated in Fairbairn’s 1860 Useful Information for Engineers, Vol. 2:
Hence the advantage gained by the gearing will be W/P = 18 x 63.75 x 80 / 6 x 8 x 12 = 158 or taking the number of cogs in each wheel W/P = 18 x 95 x 100 / 12 x 9 x 10 = 158 and as this result is quadrupled by the fixed and moveable pulleys, the power of the men applied to the handles is multiplied 632 times by the gearing and blocks. Two men are sufficient to move round the crane with 60 tonnes suspended from the extreme point of the jib.
Check out the whole article here.
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