Heatly-Gresham Engineering Co
of Bassingbourn Iron Works, Royston
of Letchworth, and of 110 Cannon Street, London.
1900 Harry Heatly established works at Bassingbourn, where some of the first London motor-cabs were made; Heatly continued to represent Gresham and Craven
1901-06 Built the Rational Cars
1903 Began the building of the Rational engine at Bassingbourn in 1.5, 3 and 6 hp sizes [1]
1904/5 Moved to Letchworth and built the first factory at Letchworth, called Gresham Iron Works. Manufactured railway materials, especially the component parts of the continuous automatic vacuum brake, and industrial oil-engines.
An associate of Gresham and Craven of Manchester
1931 exhibited their 'National' oil engines, vacuum brake exhausters and flood lighting equipment[2]
1930s Ceased trading