William Barnett (engineer)


William Hall Barnett, is described as a 'founder' in his 1836 patent, and an 'ironfounder' in his 1838 patent, and later as an engineer and gas engineer, working in Brighton, UK. He worked for many years for the Brighton and Hove General Gas Company.

Patents

His patent of 1836 is recorded in the Mechanics Magazine as "Certain improvements for generating and purifying gas for the purposes of illumination". He also contributed the lead article for the Mechanics Magazine on 23 September 1839, titled "Barnett's improved method of working gas retorts", which again relates to production of coal gas.
The patent "Obtaining Motive Power" relates to some very early work on the gas internal combustion engine, which is described in more details below.

Contribution to early gas engines

William Barnett was an engineer involved in the early development of internal combustion engines, and his work and patent are described over several pages in Dugald Clerk's book on Gas and Oil Engines. In Barnett's UK patent, which was entitled "Production of motive-power", Clerk states that "Barnett's inventions as described in his specification are so important that they require more complete description than has been accorded to earlier inventors", and he then proceeds to discuss Barnett's patent over several pages.
The patent describes three types of internal combustion engine run using gas as a fuel. These use two key inventions that were important to the early commercial gas engines.
The engines themselves are of considerable interest as precursors, not of the first commercial gas engines, but rather of the later generation of engines including Otto's engines operating on the four-stroke cycle and Dugald Clerk's engine operating on the two-stroke cycle, both with compression of the gas/air mixture in the cylinder.

Characteristics of the engines

Note that all three engines operate on the two-stroke cycle, as did most early engines. It was a remarkable leap to discover that, for internal combustion engines, the four-stroke cycle with three non-power strokes could deliver both economy and performance, see Alphonse Beau de Rochas who patented the idea in 1861, and Otto who made commercial engines using the four-stroke cycle after his earlier work with atmospheric engines. All three of Barnett's engines were vertical engines with a layout similar to steam table engines.
The displayed image of the third engine reveals a double acting engine in the style of a steam table engine. The vertical cylinder is not water cooled. There is a central exhaust port on the cylinder wall uncovered by the piston. Separate gas and air pumps operates at twice engine speed to deliver the fresh charge to either end of the cylinder and purge the cylinder of exhaust gases, but the piston compresses the charge once the exhaust port is covered.
Dugald Clerk describes several patents on the internal combustion engine between 1839 and 1854, but states that "Of these patents, by far the most important is Barnett's". Praise indeed from an eminent engineer who would subsequently receive a KBE and become a fellow of the Royal Society.
The concept of a two-stroke double acting gas engine was later taken up by Körting who launched a 350bhp engine based on this principle in 1900. It was in production for many years. Heat management required a water cooled cylinder and piston. The air pump system was arranged so that air was admitted before gas/air mixture thus improving scavenging, and a longer piston meant less of the stroke was available for the scavenging to take place. Mechanical valve operation was used on the inlet valve and on control valves for the air and gas pumps. Further details can be found in the literature.