Holt tractor

The Holt tractors were a range of continuous track haulers built by the Holt Manufacturing Company of Stockton, California which were named after company founder Benjamin Holt.

Between 1908 and 1913, twenty-seven of the first 100 Holt caterpillar track-type tractors were used on the Los Angeles Aqueduct project, which provided a good proving ground for these machines.¹

They were widely used by the British, French and American armies in the First World War for hauling heavy artillery including the BL 9.2-inch howitzer and the BL 8-inch howitzer.² Around 2,000 Holt 75s along with 698 Holt 120s and 63 Holt 60s saw military use during the war.² The French Schneider CA1 and Saint-Chamond and German A7V tanks were based on Holt tractors.

There were at least three models used for military purposes: the Holt 75, the Holt 120 and to a lesser extent the Holt 60. The Holt 75 was first produced in 1913.² It used two tracks for steering. It had a maximum speed of 15 miles per hour (24 km/h) and had a gasoline engine.³ In addition to US production 442 Holt 75s were built in Britain by Ruston & Hornsby in Lincoln.² Production of the Holt 75 was to continue post war until 1924.²

The 120 horsepower (89 kW) model had a tiller-type steering wheel at the front that was usually covered. It weighed about 18,000 pounds (8,200 kg),⁴ and was developed in direct response to a request for a heavy artillery tractor.² The prototype was produced in 1914 with production beginning in 1915.²

The Holt 60 which saw limited use in the war was introduced in 1911.²

• Holt Tractors Photo Archive: An Album of Steam and Early Gas Tractors, ISBN 978-1-882256-10-5