Who Invented the Flame Safety Lamp?
The invention of the flame safety lamp is often attributed to Sir Humphrey Davy, the renowned Cornish scientist and scholar. There is no doubt of his contribution, but it is also unfair to lay all the credit at his door; there are as many supporters for George Stephenson's claim, and others hold that it was William Clanny who developed the first truly useful safety lamp. Perhaps the fairest thing that can be said is that all three contributed to the initial development of the flame safety lamp.
Fairly typically, the contribution of non-english speaking scientists is ignored, and few have ever heard of Alexander von Humboldt, the German polymath who demonstrated the safe use of a flame light in an underground coal mine many years before the British establishment sought the help of Sir Humphrey Davy. Clanny's first lamp was possibly derived from this early, but hardly portable, example.
So the prize for the first successful underground demonstration of safe flame lighting must go to von Humboldt, a Prussian mine inspector who, after only a few years, abandoned the mining industry and went on to explore South America and document much of the continent's flora and fauna.
But this was only the beginning of the development of the safety lamp. Although none of the original developers claimed a patent on their ideas, leaving manufactures free to provide safe lighting for miners (at a price, of course!), many others patented devices and modifications to improve the basic design.
Over the years, patents have been issued in many countries for burners, locking mechanisms, relighting mechanisms and heat dissipating bonnets, as well as methods for increasing the reliability and accuracy of lamps used to detect the levels of methane in the mine air.
The constant development of flame safety lamps to meet the changing needs of miners for safe, effective lighting, and the detection of dangerous mine atmospheres has resulted in a huge diversity in lamp design and construction, which makes their collection such a satisfying pastime.
Davy attempted at least three designs of safety lamp, and reported his early results to the Royal Institution on November 9, 1815.
The manuscript lecture (still available for reference in the archives of the Royal institution) makes no reference to the use of wire gauze. The original, hand drawn figures prepared by Michael Faraday do not show a wire gauze lamp.
Interestingly, the published version of this lecture includes a drawing of a gauze-enclosed lamp, and mentions the use of gauze in the text.
The first definitive description of his lamp was made on December 31, 1815 in "Philosophical Magazine". He made no reference to previous mention of the design.
Both Stephenson's and Davy's lamps enclosed the flame. William Clanny introduced the glass globe, allowing more light to work by, although at first the durability of the glass was questioned, and some colliery officials forswore glass-globed lamps in favour of traditional Stephenson / Davy types for many years.
Clanny's first lamp, which he developed in 1813 and presented to the Royal Society in a lecture, used a water trap at the inlet and outlet to the lamp, and a set of bellows was used to force air through the lamp to keep the flame alight.
The lamp was not parctical for general use, but was of enough significance for Clanny to be awarded a Siver medal from the Royal Sociey of Arts in 1816.
Alexander von Humboldt
There is no doubt that Stephenson began work on his safety lamp in August, 1815, about the same time that Davy received a request from the Society for Preventing Accidents in Mines in Sunderland to consider ways of providing safe underground lighting.
Stephenson was working at Killingworth Pit in Northumberland at the time, and asserted to his "viewer" that he could make an automatic safety lamp. Nicholas Wood, a local tinsmith, visted Stephenson that evening and they roughed out the design of his first lamp.
He showed his lamp publicly on December 5th, 1815, demonstrating its effectiveness with pigs bladders full of methane gas.
Stephenson's lamp protected the general body of mine air from the enclosed flame with both narrow tubes and a perforated metal screen, the latter having much the same effect as the wire gauzes subsequently used by Davy.
Stephenson's Safety Lamp (after NCB, 1981)
Davy's Safety Lamp (after NCB, 1981)
Clanny's Safety Lamp (after NCB, 1981)