This business was established in 1837 as Smith & Ashby later known as Rutland Iron Works. Later still it came into the ownership of Ashby and G. E. Jeffery. In 1877 Edward Christopher Blackstone was admitted to a new partnership owning Rutland Iron Works known as Jeffery and Blackstone. Blackstone and George Mills, a member of Blackstone's wife's family, bought out Jeffery in 1882. A limited liability company, Blackstone & Co Limited, was incorporated on 29 January 1889 to take ownership of the business. Following E. C. Blackstone's death in late 1916 the business was sold to a new combine, Agricultural & General Engineers group, but retained its identity and management. Blackstone shareholders were paid with new AGE shares. Their former business continued to prosper but the profits went to support unprofitable members of the new combine. AGE turned out to be a failure from start to finish and had to be liquidated following its financial collapse in 1932. AGE shares proved worthless. Three of E. C. Blackstone's sons managed to buy back Blackstone's from the liquidator with the support of an unidentified investor. An agreement had been reached with Massey-Harris of Canada to supply them all Blackstone's agricultural machinery marked with the brand name Massey-Harris-Blackstone. In the middle of 1936 ownership of Blackstone's was taken by. Blackstone's factory remained in Stamford, Lincolnshire
Products
In 1929 AGE advertised the following Blackstone products:
Engines
In 1896 they built lamp start oil engines. By 1912 they had developed a new internal combustion engine that ran on vaporising oil and was fired by a spark. It did not need a hot bulb like most engines of the time. By 1919 they had mounted a 25 hp 3-cylinder version in a crawler tractor, which they built till 1925. By 1929 they were building diesel engines for the Agricultural & General Engineers group. Richard Garrett & Sons assembled some of these tractors. They were similar to an International 15/30.
Mergers
AGE collapsed in 1932, after which Blackstone & Co. continued as an engine builder and was taken over by R A Lister and Company in 1937 to form Lister Blackstone.
Mirrlees Blackstone Limited was formed on 1 June 1969 by the merger of Mirrlees National Limited and Blackstone & Company Limited. All were, at the time, members of the Hawker Siddeley Group.
Mirrlees Blackstone were bought by MAN Diesel, along with the diesel businesses of the collapsed GEC, although little remains. The Stockport factory has been partly demolished and replaced with a new office and warehouse facility which still serves the aftermarket for spares and servicing of Lister Blackstone engines under the MAN Diesel & Turbo tagline. The Blackstone name lives on with Blackstones F.C., a football club in Stamford.
Blackstone supplied a number of diesel engines for British Rail locomotives but these were largely unsuccessful and were not adopted.
In the 1980s, four of the well-established Paxman Valenta-engined HST trainset power cars were re-engined with Mirrlees Blackstone MB190 engines for trials. These were unsuccessful and Valenta engines were reinstalled. Eventually, in the 2000s, the fleet was re-engined with MTU V16 4000 engines.
The Class 10 was a small number of the widespread Class 08 0-6-0 diesel-electric shunter, in which a Blackstone ER6T engine was fitted instead an English Electric 6KT. They were withdrawn early.
Class 30 Type 2 locomotives were built with a Mirrlees Blackstone JVS12T but all were rebuilt as the Class 31 with the English Electric 12SVT, as also used in the Class 37.
The projected Type 3 freight Class 38 of the 1980s was considered for use of a Mirrlees MB275T. Four of the refurbished Class 37/9 at this period were rebuilt with the engine as a trial, two more used the Ruston RK270T as a comparison. In the end, the Class 38 was cancelled in favour of the Class 60.
Class 60 heavy freight Type 5 locomotives of the 1980s replaced the projected Class 38. Like the 38, these used the Mirrlees MB275T engine.. These 8 cylinder engines, compared to the more common V12 or V16 engines in this power range, were hoped to show lower operating costs owing to their simplicity.
Examples of Blackstone engines can be seen at the Anson Engine Museum near Manchester. The former Stamford Museum in Stamford, Lincolnshire, also had a Blackstone engine on display, and held an archive relating to the company.
