Description:Reverse section of 'sun & planet' engine for Coates & Co., Oil Mill, Hull, Yorkshire.
Henry Coates and John Jarratt bought this 7 horse power 'sun & planet' engine for their oil mill at Sculcoates, Kingston-upon-Hull, Yorkshire. This engine was the first double-acting engine that Boulton & Watt sold. It used one of the 15 inch cylinders from James Watt’s experimental double-cylinder engine that he set up at Soho. It was also one of the first (the very first?) to feature a perpendicular motion linking the piston rod and beam, which was precursor to the parallel motion. Note that the drawing shows the engine with the earlier rack and sector motion.
This drawing is part of the Archives of Soho collection, which is held by Birmingham City Archives [Ref. MS3147/Portfolio/5/1]