Bertram Thomas, later Bertram Thomas (Engineers)
of Worsley Street, Hulme, Manchester, 15. Telephone: Blackfriars 0905/6. Telegraphic Address: "Breaker, Manchester"
1885 (or 1879)) Company founded by brothers Bertram Thomas, Eustace Thomas and Frank Thomas, as a light engineering firm.
The company started doing wiring jobs in buildings, including Stretford Town Hall. The company made electrical switchgear for the electrical distribution network. They also diversified into other electrical equipment for catering and household equipment, such as kettles.
Bertram Thomas developed a patented storage racking system called "Tiltrack".
1937 Listed Exhibitor - British Industries Fair. "Tiltrack" Sectional Steel Storage Bins and Adjustable Shelving, Steel Cabinets and Cupboards. Electric Dinner Wagons. Carving Tables, Hot Plates, Plate Warmers. Fixed and Portable Electric Heaters, and Motor Car Pre-heaters. (Stand No. D.200) 
1939 Private company. The company was providing switchboards for tramways and light railways around Britain and overseas. In the pre-war years they also manufactured Ring Main and battery switchboards for submarines
Post-WWII focussed on the railway and Rapid Transit side of the business.
1950s-70s Made DC and AC switchgear for Rapid Transit systems in Toronto, New York, Boston, Cleveland, Chicago, Caracas, and Lisbon, amongst other cities.
1961 Electrical and mechanical engineers and contractors. Makers of switchgear and "Tiltrack" patent storage system. 450 employees. 
1963 Motor Show exhibitor. Storage and lockers. 
1968 GEC acquired English Electric.
1969 As result of GEC's acquisition of English Electric Co and AEI, Bertram Thomas became part of English Electric-Hewittic Rectifiers. Closure of the plant in Worsley Street, Manchester, and the plant in Mosley Road, Manchester
Moved to Trafford Park. Manufacture of DC Switchgear continued there until the early 1990s.