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On the stairs inside the HQ can be found the only known portrait of a remarkable engineer, Joseph Bramah. It is a fitting location, as it is thanks to Bramah and his patented beer pump that pub customers today can enjoy a fresh drink from the beer tap.
Bramah was born in Yorkshire in 1748 (some accounts say 1749). He started out as a farm labourer until his interest turned to woodwork. Apprenticed to a local carpenter, he realised that to make money and to develop his ideas he needed to gain experience in a city. After walking to London, his efforts were soon rewarded by finding employment as a cabinetmaker – and 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 residence, Osborne House on the 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.
His beer pumping system comprised 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, and 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 the American Alfred Charles Hobbs managed it; mind you, it took him more than 50 hours across 16 days! Hobbs was himself a locksmith.
The Challenge Lock can be viewed in the Science Museum in London, although it has been rebuilt since Hobbs picked it.
Bramah’s first patented lock was developed in 1784 and made by Bramah Locks, a firm that is still in business.
However, Bramah’s hydraulic press is considered his most important invention. It 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 to that in which a lever is used to increase the force exerted. The hydraulic press had many industrial applications, as it still does.
Bramah had established his own workshop by the late 1770s which trained several famous engineers including Henry Maudslay, Joseph Clement and Joseph Whitworth.
Bramah and William George Armstrong are often considered the fathers of hydraulic engineering. Armstrong was president of the IMechE and his home, Cragside in Northumberland, 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. While working in Holt Forest, Hampshire, he caught pneumonia. He died there on 9 December 1814.