Device for cutting the iron bars of a portcullis, 1588.

ITALY - JUNE 30: Copper-plate engraving from �Le diverse et artificiose machine� (The various and ingenious machines) by Agostino Ramelli (1531-c 1600) published in Paris in 1588. Ramelli served as an engineer under the Duke of Anjou and later under Henry III of France. The book has many excellently engraved copper-prints and was written in Italian and French. The prints mainly show machines for drawing water, agricultural and military purposes. A few of Ramelli's designs are linked with earlier engineers such as Hero of Alexandria. Not all of Ramelli's designs are practical, but the various types of gearing, roller-bearings, chain-transmission and other parts are still of much interest. (Photo by SSPL/Getty Images)