Geordie lamp
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The Geordie lamp (or Geordy lamp) was invented by George Stephenson in 1815 as a solution to explosions due to firedamp in coal mines.
[edit] Origin
In 1815, Stephenson was the engine-wright at the Killingworth Colliery in Durham and had been experimenting for several years with candles close to firedamp emissions in the mine. In August he ordered an oil lamp which was delivered on 21 October and tested by him in the mine in the presence of explosive gases. He improved this over several weeks with the addition of capillary tubes at the base so that it gave more light and tried new versions on 4 and 30 November. This was presented to the Philosophical and Literary Society of Newcastle on 5 December 1815.[1]
Although controversy arose between Stephenson's design and the Davy lamp (invented by Humphry Davy in the same year), Stephenson's original design worked on significantly different principles.[2] If the only way air could get to the flame was restricted (a baseplate pierced by a number of small-bore brass tubes was the usual way of doing this) and the lamp body above the flame lengthened, then the same amount of air could get to the flame, but would pass through the flow restriction at a velocity higher than the velocity of the flame in a mixture of firedamp (mostly methane) and air. This, then, prevented an explosive backblast that might light the surrounding air.
One advantage of Stephenson's design over Davy's was that if the proportion of firedamp became too high, his lamp would be extinguished, whereas Davy's lamp could become dangerously hot. This was illustrated in the Oaks colliery at Barnsley on 20 August 1857 where both types of lamp were in use.[3]
Stephenson's design used glass to surround the flame, which cut out less of the light than Davy's, where the gauze surrounded it.[4] But this also posed the danger of breakage in the harsh conditions of mineworking, a problem which was not resolved until the invention of safety glass. Stephenson tried several different designs in early years and later adopted Davy's gauze in preference to the tubes and it was this revised design that was used for most of the 19th century as the Geordie lamp.
The Geordie lamp continued to be used in the North-East of England through most of the 19th century, until the introduction of electric lighting.
[edit] The name "Geordie"
The name is possibly the route by which 'Geordie' became the familiar and affectionate epithet for North Easterners, deriving from a diminutive form of the inventor's first name, George.[5] However, using two Brockett serials in their Chronological order, the North Eastern pitmen appear to have shared the name Geordie with the Stephenson lamp[6][7]
[edit] See also
- ^ Smiles, Samuel (1862), Lives of the Engineers, III, pp. 119–127
- ^ Stephenson, George (1817), A description of the safety lamp, invented by George Stephenson, http://books.google.co.uk/books?id=SYkIAAAAQAAJ&printsec=frontcoveraccess-date=2011-12-11
- ^ Smiles 1862, p. 131
- ^ History of Miners' Lamps, http://www.welshminerslamps.com/info_lamp_history.shtml, retrieved 2011-12-11
- ^ He was known locally as Geordie the engine-wright. Smiles, Samuel (1862). "chapter 8". The lives of the engineers. III.
- ^ Brockett, John Trotter (1829). A Glossary Of North Country Words In Use With Their Etymology And Affinity To Other Languages And Occasional Notices Of local Customs And Popular Superstitions. E. Charnley. pp. 131. "GEORDIE, George—a very common name among the pitmen. “How ! Geordie man ! how is’t”";
- ^ Brockett, John T. (1846). A Glossary of North Country Words. pp. 187. "GEORDIE, George—a very common name among the pitmen. “How ! Geordie man ! how is’t” The Pitmen have given the name of Geordie to Mr George Stephenson's lamp in contra-distinction of the Davy, or Sir Humphry Davy's Lamp."
