In the late 1850s John Smith junior became interested in steam-powered vehicles for agricultural use. His early engines were based on two patents of J.A. Williams of Baydon in Wiltshire. The first patent was number 1766 and was taken out in 1855 and the second was number 285 from 1857. Both patents were described as being for “machinery or apparatus for cultivating land”. William’s patent apparatus allowed the engines to be self-moving by the use of a pitch chain, which connected the drive from the crankshaft to the rear wheels.

John started producing partly self-propelling ploughing machines in 1857. His early machines were guided (steered) by a horse, which also helped to pull the machine up steep hills. In October 1857 such a machine was produced for S & G Lewis of Audley, near Newcastle in Staffordshire. It was powered by a 6 hp. steam engine and appears to have been satisfactory.

In November of that year he exhibited three engines at the Bushbury Agricultural Society’s show along with ploughing tackle and a threshing machine. The engines were a 7 hp. portable, a 10 hp. portable, “made locomotive by William’s patent apparatus” and a 12 hp. tank engine. 

A John Smith ploughing engine.

An account of John Smith’s engines can be found in J.  A. Clarks’ “Account of the application of steam power to the cultivation of the land”; Royal Society Journal, Engineering, Series 1, Volume 20, page 208. In the account Clark describes an engine of nominally 10 hp., but actually 25-30 hp., as follows:

“A horizontal tubular boiler is mounted upon a wrought-iron framing, and balanced upon two plummer-blocks, so that it can be instantly and easily adjusted to any level by means of a screw under the command of the driver, who has a spirit level to guide him. The cylinders are not fixed to the shell of the boiler but are placed within the framing beneath it; the steam passing by a pipe from the top of the high steam dome and through a stuffing box in one of the plummer-block bearings…while the exhaust steam is conducted to the chimney by a short piece of flexible pipe. The water is supplied to the boiler by the feed pipe passing through a stuffing box in the other plummer-block bearing.”  

The front wheels were 3ft 6 inches in diameter and the rear wheels were 6 ft in diameter and 12 inches wide. The wheelbase was about 9 ft. 

An impression of a horse-steered ploughing machine.

The vehicle weighed 7 tons and the maximum boiler pressure was 120 lb per square inch, but it was normally operated at 60 lb per square inch and was horse-steered.

Clark was told by John Smith that:

“My price for an 8-horse single cylinder engine, constructed in the usual way, with Lowmoor plates in the fire box and copper piece to receive the tubes at the firebox end is £125. An 8-horse engine with double cylinders, £235. Extra for making locomotive by means of William’s pitch-chain, £25.”

For ploughing, John Smith recommended an 8 hp. “engine built with frame, water tank, reversing gear link motion, travelling wheels 12 inches wide, and made locomotive with the pitch chain, for £335; or if with my patent balanced boiler etc., £360. The 10-horse engine costs £420”.

John’s engines were starting to be noticed. He won a silver medal for his 12 hp. steam ploughing machine at the Staffordshire Agricultural Society’s Show at Lichfield in September 1858.