Engraved diagram showing a system of pistons, pivots, wheels, plates, rods and pins, which cause wind to power an organ. The arms or sails of the windmill, 'urged by the wind, drive round the wheel,...the rod...will be driven round, so that the wheel...and the pegs attached to it will strike the plate...at intervals and raise the piston; when the peg recedes, the piston, descending, will force out the air in the box...into the tubes and pipes, and produce the sound. We may always move the frame which contains the rod...towards the prevailing wind, that the revolution may be more rapid and uniform.' Illustration from 'Gli artifitiosi et curiosi moti spiritali di Herrone' (commonly called 'Pneumatics') by Hero of Alexandria, published in Ferrara in 1589.
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