Storey’s Gate Tavern once stood where IMechE’s London Headquarters now stands. It is home to the only known portrait of a remarkable engineer, Joseph Bramah. It is fitting that this is its location, as it is thanks to Bramah and his patented beer pump that customers can today enjoy a fresh drink from the beer tap!
Bramah was born in Stainborough, Yorkshire, 13 April 1748 (or 1749). He started work as a farm labourer until his interest turned to wood-working. Apprenticed to a local carpenter he realised that to make money and to develop his ideas he needed to gain experience in a city. Walking from Stainborough to London his efforts were soon rewarded by finding employment as a cabinet-maker; one of his jobs was to fit water closets. This led to his first patent of 1778 for a water-closet. Apparently, one of these can be found working in Queen Victoria’s summer residence, Osborne House, Isle of Wight.
Bramah worked on pumps and water supply which led to his involvement in the brewing industry. He became interested in the problem of serving fresh beer in taverns and devised an ingenious method of pumping beer from the cellar to the parlour. The principle of his invention was that if pressure is applied to a contained fluid it will move rather than compress. He deduced that by applying this principal beer could be moved up piping. His beer pumping system was comprised of sets of casks connected to a forcing pump. The sets of casks could be cleaned using a water cistern and pressure was applied to the stored alcohol by a loaded piston. In his patent Bramah also specified a new method for extruding tin and lead under pressure to make continuous pipes which he intended to use in his beer pumping system.
His ‘Challenge Lock’ was finished in 1790, it took pride of place in his shop window with the inscription “The artist who can make an instrument that will pick or open this lock shall receive 200 guineas the moment it is produced.” It was not until 1851, during The Great Exhibition, that American Alfred Charles Hobbs managed it; mind you it took him over 50 hours across 16 days! Hobbs was himself a locksmith. Bramah’s first patented lock was developed in 1784 and put into production by Bramah Locks; you may have seen their vans if you have walked around London or Essex as the firm is still going. His second patented design was in 1798. The ‘Challenge Lock’ can be viewed in the Science Museum, London, although it has been rebuilt since Hobbs picked it.
However, his hydraulic press is considered his most important invention. The hydraulic press depends on Pascal’s principle, that pressure throughout a closed system is constant. Bramah was granted a patent for his hydraulic press in 1795. The press had two cylinders and pistons of different cross-sectional areas. If a force was exerted on the smaller piston, this would be translated into a larger force on the larger piston. The difference in the two forces would be proportional to the difference in area of the two pistons. Therefore, the cylinders act in a similar way that a lever is used to increase the force exerted. The hydraulic press had many industrial applications, it still does today and it is still called the Bramah Press. In the 1790s, just as Bramah was bringing his concepts to successful fruition, the field of hydraulic engineering was an almost unknown science.
He had established his own workshop by the late 1770s which trained a number of famous engineers including Henry Maudslay (machine tool innovator, tool and die maker), Joseph Clement (engineer and industrialist) and Joseph Whitworth (engineer, entrepreneur, inventor and philanthropist). Partly due to the precision requirements of his locks, Bramah developed machine tools to assist manufacturing processes. He and Maudslay worked together on a number of innovative machines that made the production more efficient, and were applicable to various fields of manufacture. Another invention was an automatic bank note numbering system.
Both Bramah and William George Armstrong are often considered the fathers of hydraulic engineering, both were pioneers in the field. The latter was President of IMechE and his home of Cragside (it is open to the public) was the first domestic building to be powered by hydro-electricity. One of Bramah’s last inventions was a hydrostatic press capable of uprooting trees. Whilst working in Holt Forest, Hampshire, Bramah caught pneumonia. He died there on 9th December 1814.