Grace's Guide is the leading source of historical information on industry and manufacturing in Britain. This web publication contains 135,548 pages of information and 217,108 images on early companies, their products and the people who designed and built them.
1880 the Leicester firm became Joseph Jessop and Son.
Messrs Jessop and Son were the sole makers in Great Britain of engines fitted with the Collman gear, and had constructed and installed 750 by 1888.
1888 Compound condensing engines fitted with Collman's valve gear installed at the grain store of the Guinness brewery, Dublin. The cylinders are 14 and 20 inch with a stroke length of 28 inches. The engines give 87 revolutions per minute and transmit their power from the fly wheel to the counter shaft by two steel wire ropes running in leather-lined grooves. The working steam pressure is 150 lbs and the the indicated horse-power is 150. 
1896 Two horizontal compound steam engines of 200 HP with Collmann valve gear, for the Southall margarine factory of Otto Monsted.