Who invented the mining safety lamp, Davy or Stephenson?

Materials World magazine
,
3 Nov 2015

Frank James recounts the tale behind the invention of the mining safety lamp, 200 years ago.

Towards the end of 2015, we will be marking the bicentenary of the simultaneous, and almost certainly independent, inventions of two versions of the miners’ safety lamp. The two inventors were Humphry Davy, Professor of Chemistry at the Royal Institution between 1801 and 1812, and George Stephenson, a mining engineer from Newcastle. 

During the 18th Century, the counties of Northumberland and Durham produced more coal than any other region in the British Isles. Even by the middle of the 19th Century, following the expansion of mining elsewhere, the north-east still produced more than a fifth of the nation’s coal. But such production came at a heavy cost to the lives of mineworkers. The opening years of the 19th Century saw an exponential increase in coal mine fatalities caused by the explosion of what was then termed fire-damp, now known as methane (CH4). On 25 May 1812, 92 men and boys (including four aged under 10) were killed by an explosion at Felling colliery, near Gateshead. This was in the parish of Jarrow-with-Heworth, whose Rector, John Hodgson, was horrified at the loss of life, especially as virtually all the victims were buried in Heworth church. 

Taking action 

One result of this disaster was the formation of ‘A Society For Preventing Accidents In Coal-Mines’, generally known as the Sunderland Society. Its object to raise funds to provide premiums ‘for the discovery of new methods of lighting and ventilating mines’ was never realised. However, in early 1814, the Society issued its first report, which argued that ‘it is to scientific men only that we must look up for assistance in providing a cheap and effectual remedy’. Doubtless with this injunction in mind, Humphry Davy was approached at the Royal Institution, founded in 1799 with the practical remit of promoting ‘the application of science to the common purposes of life’ – an agenda which Davy fully supported. 

During the week beginning 9 October, Davy, helped by the Royal Institution’s laboratory assistant, Michael Faraday, commenced an intense period of research on the problem. By the end of the month, Davy believed that he had developed a safe lamp, which was basically a standard horn lamp with very narrow glass tubes acting as a chimney. He worked on the principle of endeavouring to construct a lamp which would allow light to pass, but would reduce the temperature of the heat reaching the surrounding atmosphere to below the point which would ignite the fire-damp. He told his patron, the President of the Royal Society of London, Joseph Banks, of his work for which Banks congratulated him heartily ‘on defending Society from a Tremendous Scourge of humanity’. With the same principle in mind, Davy developed other lamps with a variety of chimney shapes and air intakes. 

So confident was he of having achieved success, it was agreed that the paper describing his work would be read to the Royal Society of London on 9 November and the prototype lamps were displayed in Banks’s Soho Square house. Although the illustrations for Davy’s paper were engraved (at some expense) for publication in Philosophical Transactions, the paper as read was never published, since Davy and Faraday continued work and soon developed the idea of what Davy called a fire sieve. This was a series of nested metal cylinders or rectangles, which would absorb the heat and thus reduce the external temperature of the lamp. From this it was only a short time before Davy realised that the same effect could be obtained by just using wire gauze, telling Hodgson right at the end of December, ‘When a candle or lamp is enclosed in a wire gauze cylinder and introduced into an explosive mixture the flame of the wick is extinguished but the mixed gas burns steadily within the wire gauze vessel… I can confine this destructive element flame like a bird in a cage.’ A few days later, Davy sent Hodgson five of his lamps and, on 9 January 1816, Hodgson and others descended into Hebburn colliery (also in his parish) to test the lamps – successfully.

Competitive complications

Reports of Davy’s lamp had started circulating by early November and this prompted an announcement early that month at a meeting of the Newcastle committee for the coal trade that Stephenson, since September, had been developing and using a safe lamp in Killingworth colliery where he was engineer. Like Davy’s lamp, Stephenson’s underwent developments through October and November (though these are less well documented than Davy’s) and, by the middle of that month, it was clear that there was room for a serious priority dispute. Davy visited the north-east twice during 1816 and the triumphalist attitude he displayed towards his lamp, and his highly dismissive views of Stephenson’s, turned the dispute acrimonious and personal. In the north-east, Davy had considerable establishment support from figures such as Robert Gray, Rector of Bishopwearmouth, Hodgson, the Bishop of Durham, and John Lambton, later Earl of Durham. He told Lambton, 'I hope you will not blame me for not taking any notice of the attacks of my enemies in the North. I have no desire to go out of my way to crush gnats that buzz at a distance, and do not bite me, or to quarrel with persons who shoot arrows at the moon’.  

To take public notice of Stephenson would have invited comment on Davy’s work – much better to remain silent in public and abuse him in private. In a clearly concerted move to outflank Stephenson, on 11 October 1817, a powerful group of mine owners, led by Lambton, publicly presented Davy with a plate worth £2,500 while, the following month, Banks and other officers of the Royal Society of London issued a statement from Banks’ house rebutting all of Stephenson’s claims. Stephenson’s supporters could only raise 600 guineas and there was no possibility that Stephenson could either follow or contradict the rhetoric emanating from Soho Square.

Science stands above

From this controversy emerged the idea, expressed by Faraday, that the Davy lamp was a ‘mark of subjection set by science in the strongest holds of nature’. Quite what was scientific about the lamp is not clear, but claiming it for science helped undermine Stephenson’s position, since, as someone with no scientific background at all, he could not make the same claim. One consequence of the controversy was that Davy refrained from seeking to patent his lamp in case Stephenson mounted a successful challenge. Instead, Davy adopted the rhetoric of giving his invention freely for the benefit of humanity and ensured that his iconography included the lamp.

In terms of its practical impact, aside from saving lives, both lamps allowed for the exploitation of deeper coal seams (where there was more fire-damp) and, thus, an increase in production. The statistics for the north-east coal field for the number of miners killed per million tonnes of coal extracted shows equally steep exponential rise and fall either side of 1815 and a continuing gradual decline thereafter.

The evidence from this episode illustrates the wide range of contingencies, interests and knowledge involved in mining safety. Religious, political, legal, economic, rhetorical, business, media, scientific and engineering considerations all played their part. Mostly working for an avowed benefit for humanity (though occasionally not), these interests during the 19th Century and beyond cohered to improve safety in mines, to reduce the frequency between the necessity for long cortèges and at the same time increase coal production, which allowed a continued expansion of industrialisation. Safety was not, is not, a stand-alone issue, but an integral part of culture and society.

See Frank James' lecture on "The State, Science and Humphrey Davy" at https://www.youtube.com/watch?v=FjD6tiqR-Do