The origins of John I. Thornycroft & Co.Ltd. can be traced back to 1864 in Chiswick, London. In 1871 they produced a steam powered launch which reached an unprecedented speed of 18 knots. From their experience with further vessels, they decided to apply this to a vehicle and in 1896 emerged van number 1. In 1901 there was a steam powered double decker working in London. In 1904 they made their first petrol engined car and lorries came two years later.
The ‘J’ type was introduced in 1912 as a 4½ tonner having a 30 h.p. 4 cylinder engine, cone clutch and 4 speed gearbox. It was the first Thornycraft to have a ‘live’ rear axle – previous models were chain driven. Like its competitors a straight chassis frame was used and both goods and passenger bodies were fitted. In 1918 a more powerful. 40 h.p. engine was introduced and in the following year, a longer wheelbase was offered increasing the variety of bodywork that could be fitted.
In 1919, Portsmouth Corporation bought 10 ‘J’-type chassis and had them equipped with 36 seat double deck bodies. These were typical of the period and followed horse bus design down to the narrower lower deck to allow the front wheels to turn! This resulted in having 8 inward facing seats on each side but allowed 9 pairs of forward facing seats in the wider upper deck. In addition 2 more passengers could be accommodated alongside the driver. This was an exposed position as there were no windscreens but very often the driver had a tarpaulin which he could tie round his neck in wet weather, similar protection was provides in the upper deck, for the passengers. A porch was built over part of the platform to give the conductor shelter.
The ‘J’ type was introduced in 1912 as a 4½ tonner having a 30 h.p. 4 cylinder engine, cone clutch and 4 speed gearbox. It was the first Thornycraft to have a ‘live’ rear axle – previous models were chain driven. Like its competitors a straight chassis frame was used and both goods and passenger bodies were fitted. In 1918 a more powerful. 40 h.p. engine was introduced and in the following year, a longer wheelbase was offered increasing the variety of bodywork that could be fitted.
In 1919, Portsmouth Corporation bought 10 ‘J’-type chassis and had them equipped with 36 seat double deck bodies. These were typical of the period and followed horse bus design down to the narrower lower deck to allow the front wheels to turn! This resulted in having 8 inward facing seats on each side but allowed 9 pairs of forward facing seats in the wider upper deck. In addition 2 more passengers could be accommodated alongside the driver. This was an exposed position as there were no windscreens but very often the driver had a tarpaulin which he could tie round his neck in wet weather, similar protection was provides in the upper deck, for the passengers. A porch was built over part of the platform to give the conductor shelter.
The Portsmouth buses had their original bodies replaced in 1925 by ones removed from London General ‘B’ type buses, giving them another 3 years life. Upon withdrawal, one of these was fortunately preserved by the Corporation and still appears on the road occasionally.
