of 18 New Cavendish Street, London, W1. Telephone: Welbeck 1212. Cables: "Schall, Phone, London"
1939 Company incorporated. Formerly Solus Electrical Ltd
1945 Established Solus Electronic Tubes as a subsidiary making X-ray tubes
1946 Amalgamated with Schall and Son Ltd - presumably forming Solus-Schall Ltd
1947 Listed Exhibitor - British Industries Fair. Manufacturers of X-ray and Electro Medical Apparatus including Superficial Medium and Deep Therapy Apparatus, X-Ray Apparatus for Industrial and Laboratory Research Work and all Accessory Equipment and X-Ray Tubes and Valves. (Olympia, Ground Floor, Stand No. D.1701) 
1961 Offered Trans-Weigh equipment for measuring weight and control of loads on conveyor belts