International Harvester 22/36 tractor, 1931.
© Science Museum / Science & Society Picture Library
In 1921 the International Harvester Corporation (IHC) introduced the next generation of their lightweight designs with the 15/30, and in 1929 they introduced an upgraded version, the 22/36, (though sometimes it was still labelled 15/30). IHC had adopted Fordson's cast unit construction, but had modified the idea by providing a cast iron hull forward of the gearbox in which the engine sat separately, unlike the Fordson where the engine was an integral part of the tractor's structure. This did offer certain benefits when it came to maintenance. A smaller version, the 10/20, was very popular in Britain. The 22/36 ('New 15/30') ceased production in 1934.