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Blackstone and Co of Rutland Engineering Works (Rutland Ironworks), Stamford.
1889 January 29th. Jeffery and Blackstone became a limited company and changed their name to Blackstone and Co. The directors were:
In addition there were the following shareholders:
1890 June. Royal Agricultural Society’s Disintegrator and Grist Mill Trials. 
1894 June. Royal Agricultural Society's Show. Mower, root cutter, turnwrest plough and fly brush or dresser. 
1896 Commenced the manufacture of the 'Reliance' oil engine previously made by Carter Brothers (of Billingshurst).
1900 Paris Exhibition. Description of gas and oil engines shown. 
1911 Smithfield Club Show. Exhibited portable and stationary oil engines, swath turners, a horse rake and turnip cutters. 
1914 Specialities: Haymaking and Agricultural Machinery, Vertical Stone Mills for grinding corn and other substances.
Post WWI. Produced tractors in tracked and wheel versions with a three-cylinder engine
1919 Became part of Agricultural and General Engineers.
1920 Showed a caterpillar type oil-driven tractor that started from cold on paraffin. It had a 25 hp engine with three-speeds and a reverse and could be used for driving stationary machinery. They also showed sixteen sizes of their crude oil engine with one of 75bhp. There were also a combined swath turner, tedder and side rake. All these were at the Darlington Agricultural Show. 
1920 At Darlington Royal Agricultural Show exhibited a tractor. 
1931 Blackstone's entered into a mutual agreement with Ruston and Hornsby (Lincoln & Grantham) not to produce engines which would duplicate each other's range.
1936 A substantial shareholding in Blackstone's was acquired by R. A. Lister and Co and the 2 companies entered into a cooperative agreement. Ernest Blackstone and Harold Blackstone retired from the board 6 months later. See Lister-Blackstone products.
1937 Oil-engine manufacturers. 
1939 A working arrangement agreed with Brush Electrical Engineering Co whereby the Brush horizontally opposed diesel engines would be sold exclusively by Blackstone and Co; these complemented the existing Blackstone engines, extending the range which covered 3 h.p to 2000 h.p.
1945 More than 206,000 Petrol, oil and gas engines produced since 1896. Display at Anson Engine Museum.
1961 Manufacturers of diesel engines, electrical generating sets and agricultural machinery. 1,250 employees.