Cross Manufacturing Co
of Combe Down, Bath, Somerset, and Devizes, Wiltshire.
1923 Formed by Roland Claude Cross
1933 Private company.
1937 Details of the valve with drawings.
1938 Company made public.
1961 Experimental and development engineers and manufacturers of aircraft and other components. 110 employees. 
1961 Developed an engine for the Cotton Cougar 250cc scrambler motorcycle.
2017 The firm is a prominent supplier of high technology seals for turbines and other machinery, rolled sections in a variety of steel and other alloys, locking rings, etc., with factories in Bath and Devizes. See Cross Manufacturing Co. website - Heritage and Cross Manufacturing Co. website - Home page.