Irishman Stephan Alley and his Scots partner John Alexander MacLellan opened the Sentinel Engineering Works in 1876. They began by producing a range of valves for industrial users, but the business soon outgrew their small premises. So in 1880 the company moved to a site in Polmadie, Glasgow. Here a far greater variety of work was undertaken including the building of compressors, lighting plant, marine and stationary engines, ships' machinery and most important of all - prefabricated ships. Whole vessels were built and then stripped down into sections for delivery to customers all over the world. In fact the firm operated the first 'shipyard on dry land', something for which the Americans often received credit.

In 1903 Alley and MacLellan acquired the business of Simpson and Bibby of Horsehay, Shropshire, who had been working in the production of steam road vehicles. Their work was transferred to Polmadie and in 1905 the first Sentinel Steam Waggon appeared. Note the spelling of 'Waggon'. Sentinel built steam waggons - leaving other, lesser, manufacturers to build steam wagons!. The range of road vehicles rapidly expanded and in 1915 waggon production moved to a new plant in Shrewsbury. Here the highly successful range of tractors, buses and waggons continued in production until 1915 when the last 'S type' steam waggon was built. The Sentinel steam road vehicles were a match for any internal combustion engined vehicle of the time, some waggons being capable of 60 mpg.

The company turned its attention to railways in 1923 with the building of the first in a long line of shunting locomotives and railcars. All were to employ the familiar poppet valve engine in the same manner as the vehicles. Steam production being taken care of by the Sentinel high pressure, water tube, vertical boiler. In 1926-27 a gearbox was introduced, drive being passed to the wheels by roller chains.

In 1956 Sentinel was taken over by Rolls Royce Ltd who built diesel engines and diesel powered railway locomotives at the plant from 1959 to 1971. Rolls Royce had also taken over the diesel engine business of Yorkshire Engine Co. in the same year. Rolls Royce diesel engine division was later transferred to Massey-Ferguson.

Examples at Quainton

Examples Previously at Quainton