Jean Chretien


Jean Chrétien (b.1834)
c.1860 Invented a travelling steam crane in which the hook was raised and lowered by a steam-operated piston built into the jib. The travel of the chain was multiplied by the use of pulleys, in the manner of Armstrong's hydraulic jigger. A scale model of the crane was shown at the 1867 Paris Exhibition, and is now displayed at the Musée des Arts et Metiers.
Note: Direct-acting steam cranes were also made by Robert Morrison and Co. These were fixed, not mobile, and had a simple direct-acting ram without the multiplying 'jigger' arrangement used by Chretien.