The tin miners in Cornwall used moist clay to fix candles to their hard hats and when they and other Europeans immigrated to America they brought their many ingenious adaptations with them. They were used of course only in gas free coal mines and rock mines in America.
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Old Wolf Safety Lamp
John Kinnear Photo |
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Oil wick lamps were common and useful for many centuries in mines, utilizing animal fat and eventually vegetable oils. Their original wicks were animal hair which was ultimately replaced by linen or cotton. Many of these "tunnel lamps" and "frog lamps" have survived in collections in Germany and other parts of Europe.
In 1853 a Polish chemist named Lukasiewicz invented the kerosene lamp which became widely used in western European mines, the kerosene later replaced with paraffin. In 1862 a German chemist named Fredrich Wohler produced calcium carbide and discovered that by adding water acetylene gas was given off which burned steadily with a bright flame. Thirty years later a Canadian inventor, Thomas Willson, found a cheap commercial way to produce calcium carbide and sold his patent to Union Carbide Company of the U.S. The carbide lamp industry grew rapidly and the lamp was popular, being 10 times brighter than an oil lamp, but being an open flame there was still a danger of explosion in certain mines.
Around 1750 an English mining engineer named Carlisle Spedding invented what was felt to be a "safe working light" for gassy mines. Dubbed the "Spedding Mill" it was a piece of flint held against a rotating steel disc. It was generally operated by a young child cranking out a cascade of bright sparks from the disc. The results were poor but supposedly safe light. The thought of some child cranking out showers of sparks in a gassy mine makes the hair stand up on my neck! The Spedding Mill was also a means of detecting firedamp as the gas caused the sparks to turn deep red! Used for 70 years it was not infallible and many explosions were attributed to it including one that ironically killed Carlisle Spedding himself in 1755.
As the carnage resulting from disasters at collieries continued inventors and scientists were pressed to come up with a safe light. Enter then Sir Humphry Davy, a noted scientist who, once he had studied the problem was optimistic he could solve it. In his experiments he discovered that the flame of burning gases would not pass through apertures of a certain diameter. Experimenting with fine wire gauze he demonstrated that a closed top cylinder placed around a wick would successfully confine and cool the flame below the ignition temperature of methane.
An engineer named John Buddle had the dubious honour of proving the lamp's effectiveness in a gassy atmosphere underground. The test was successful much to Buddles relief whereupon he uttered the classic statement: "At last the monster has been subdued".
The Davy lamp was copied and modified by many like Wolf of Germany and Clanny of England. Davy was urged to patent the working principle but he never did insisting that: "I never thought of such a thing, my sole object was to serve the cause of humanity and if I succeeded, I am amply rewarded in the gratifying reflection of having done so."
Well, Sir Davy, you did indeed succeed in serving the cause of humanity and until Thomas Edison's lightweight alkaline battery came along you made the treacherous underground world of the coal miner a lot safer place.