Description:Reverse copy of the ground plan of the engine and two boilers.
This was a typical sun & planet engine for a cotton mill. It was ordered by John Pooley and his partners for their cotton mill in Hulme, South Manchester in 1798. The engine was of 24 horses power, with a 25¼ inch cylinder, 6 foot stroke, and the parallel motion linking the piston rod to the beam. In 1803 to 1804 the power of the engine was increased to 30 horses, and it was set to powering fire extinguishing apparatus made by Boulton & Watt as well as the cotton spinning machinery.
The coloured drawings were sent to the engineer who put up the engine, Isaac Perrins. They were later returned to Boulton & Watt in order to avoid rival engineers getting hold of them. The reverse drawings, made on the copying press invented by James Watt, were kept in the Drawing Office at Soho Manufactory. [Scale: 1/3 of an inch to the foot]
This drawing is part of the Archives of Soho collection, which is held by Birmingham City Archives [Ref. MS3147/Portfolio/5/158]