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The Davy lamp is a safety lamp used in flammable atmospheres, invented in 1815 by Sir Humphry Davy. [1] It consists of a wick lamp with the flame enclosed inside a mesh screen. It was created for use in coal mines, to reduce the danger of explosions due to the presence of methane and other flammable gases, called firedamp or minedamp.
German polymath Alexander von Humboldt, working for the German Bureau of Mines, had concerns for the health and welfare of the miners and invented a kind of respirator and "four lamps of different construction suitable for employment in various circumstances. The respirator was to prevent the inhaling of injurious gases, and to supply the miner with good air; the lamps were constructed to burn in the most inflammable kind of fire-damp without igniting the gas. They were the forerunners of Davy's later invention, and were frequently made use of by the miners." [2]
Davy's invention was preceded by that of William Reid Clanny, an Irish doctor at Bishopwearmouth, who had read a paper to the Royal Society in May 1813. The more cumbersome Clanny safety lamp was successfully tested at Herrington Mill, and he won medals, from the Royal Society of Arts. [3]
Despite his lack of scientific knowledge, engine-wright George Stephenson devised a lamp in which the air entered via tiny holes, through which the flames of the lamp could not pass. A month before Davy presented his design to the Royal Society, Stephenson demonstrated his own lamp to two witnesses by taking it down Killingworth Colliery and holding it in front of a fissure from which firedamp was issuing. [4]
The first trial of a Davy lamp with a wire sieve was at Hebburn Colliery on 9 January 1816. [5] A letter from Davy (which he intended to be kept private) describing his findings and various suggestions for a safety lamp was made public at a meeting in Newcastle on 3 November 1815, [6] and a paper describing the lamp was formally presented at a Royal Society meeting in London on 9 November. [7] For it, Davy was awarded the society's Rumford Medal. Davy's lamp differed from Stephenson's in that the flame was surrounded by a screen of gauze, whereas Stephenson's prototype lamp had a perforated plate contained in a glass cylinder (a design mentioned in Davy's Royal Society paper as an alternative to his preferred solution). [7] For his invention Davy was given £2,000 worth of silver (the money being raised by public subscription), whilst Stephenson was accused of stealing the idea from Davy, because the fully developed 'Geordie lamp' had not been demonstrated by Stephenson until after Davy had presented his paper at the Royal Society, and (it was held) previous versions had not actually been safe. [6] [8] [lower-alpha 1]
A local committee of enquiry gathered in support of Stephenson exonerated him, showing that he had been working separately to create the Geordie lamp, [10] and raised a subscription for him of £1,000. [11] Davy and his supporters refused to accept their findings, and would not see how an uneducated man such as Stephenson could come up with the solution he had: Stephenson himself freely admitted that he had arrived at a practical solution on the basis of an erroneous theory. [11] In 1833, a House of Commons committee found that Stephenson had equal claim to having invented the safety lamp. [11] Davy went to his grave claiming that Stephenson had stolen his idea. The Stephenson lamp was used almost exclusively in North East England, whereas the Davy lamp was used everywhere else. The experience gave Stephenson a lifelong distrust of London-based, theoretical, scientific experts. [12] [lower-alpha 2]
The lamp consists of a wick lamp with the flame enclosed inside a mesh screen. The screen acts as a flame arrestor; air (and any firedamp present) can pass through the mesh freely enough to support combustion, but the holes are too fine to allow a flame to propagate through them and ignite any firedamp outside the mesh. The Davy lamp was fuelled by oil or naphtha (lighter fluid). [13]
The lamp also provided a test for the presence of gases. If flammable gas mixtures were present, the flame of the Davy lamp burned higher with a blue tinge. Lamps were equipped with a metal gauge to measure the height of the flame. Miners could place the safety lamp close to the ground to detect gases, such as carbon dioxide, that are denser than air and so could collect in depressions in the mine; if the mine air was oxygen-poor (asphyxiant gas), the lamp flame would be extinguished ( black damp or chokedamp). A methane-air flame is extinguished at about 17% oxygen content (which will still support life), so the lamp gave an early indication of an unhealthy atmosphere, allowing the miners to get out before they died of asphyxiation.[ citation needed ]
In 1816, the Cumberland Pacquet reported a demonstration of the Davy lamp at William Pit, Whitehaven. Placed in a blower "... the effect was grand beyond description. At first a blue flame was seen to cap the flame of the lamp, – then succeeded a lambent flame, playing in the cylinder; and shortly after, the flame of the firedamp expanded, so as to completely fill the wire gauze. For some time, the flame of the lamp was seen through that of the firedamp, which became ultimately extinguished without explosion. Results more satisfactory were not to be wished..." [14] Another correspondent to the paper commented "The Lamp offers absolute security to the miner... With the excellent ventilation of the Whitehaven Collieries and the application of Sir HUMPHRY's valuable instrument, the accidents from the explosion of' (carburetted) 'hydrogene which have occurred (although comparatively few for such extensive works) will by this happy invention be avoided". [14]
However, this prediction was not fulfilled: in the next thirty years, firedamp explosions in Whitehaven pits killed 137 people. [15] : 139 More generally, the Select Committee on Accidents in Mines reported in 1835 that the introduction of the Davy lamp had led to an increase in mine accidents; [11] : 130 the lamp encouraged the working of mines and parts of mines that had previously been closed for safety reasons. [16] For example, in 1835, 102 men and boys were killed by a firedamp explosion in a Wallsend colliery working the Bensham seam, described at the subsequent inquest by John Buddle as "a dangerous seam, which required the utmost care in keeping in a working state", which could only be worked with the Davy lamp. The coroner noted that a previous firedamp explosion in 1821 had killed 52, but directed his jury that any finding on the wisdom of continuing to work the seam was outside their province. [17]
The lamps had to be provided by the miners themselves, not the owners, as traditionally the miners had bought their own candles from the company store. Miners still preferred the better illumination from a naked light, and mine regulations insisting that only safety lamps be used [15] : 139 were draconian in principle, but in practice neither observed nor enforced. After two accidents in two years (1838–39) in Cumberland pits, both caused by safety checks being carried out by the light of a naked flame, the Royal Commission on Children's Employment commented both on the failure to learn from the first accident, and on the "further absurdity" of "carrying a Davy lamp in one hand for the sake of safety, and a naked lighted candle in the other, as if for the sake of danger. Beyond this there can be no conceivable thoughtlessness and folly; and when such management is allowed in the mine of two of the most opulent coal-proprietors in the kingdom, we cease to wonder at anything that may take place in mines worked by men equally without capital and science" [15] : 140
Another reason for the increase in accidents was the unreliability of the lamps themselves. The bare gauze was easily damaged, and once just a single wire broke or rusted away, the lamp became unsafe. Work carried out by a scientific witness and reported by the committee showed that the Davy lamp became unsafe in airflows so low that a Davy lamp carried at normal walking pace against normal airflows in walkways was only safe if provided with a draught shield [18] : 13–17 (not normally fitted), and the committee noted that accidents had happened when the lamp was "in general and careful use; no one survived to tell the tale of how these occurrences took place; conjecture supplied the want of positive knowledge most unsatisfactorily; but incidents are recorded which prove what must follow unreasonable testing of the lamp; and your Committee are constrained to believe that ignorance and a false reliance upon its merits, in cases attended with unwarrantable risks, have led to disastrous consequences" [11] : 131 The "South Shields Committee", a body set up by a public meeting there [19] (in response to an explosion at the St Hilda pit in 1839) [20] to consider the prevention of accidents in mines had shown that mine ventilation in the North-East was generally deficient, with an insufficient supply of fresh air giving every opportunity for explosive mixtures of gas to accumulate. [18] : 28–36 [lower-alpha 3] A subsequent select committee in 1852 concurred with this view; firedamp explosions could best be prevented by improving mine ventilation (by the use of steam ejectors: the committee specifically advised against fan ventilation), which had been neglected because of over-reliance on the safety of the Davy lamp. [21] : viii
The practice of using a Davy lamp and a candle together was not entirely absurd, however, if the Davy lamp is understood to be not only a safe light in an explosive atmosphere, but also a gauge of firedamp levels. In practice, however, the warning from the lamp was not always noticed in time, especially in the working conditions of the era. [22]
The Regulation and Inspection of Mines Act of 1860 therefore required coal mines to have an adequate amount of ventilation, constantly produced, to dilute and render harmless noxious gases so that work areas were – under ordinary circumstances – in a fit state to be worked (areas where a normally safe atmosphere could not be ensured were to be fenced off "as far as possible"): it also required safety lamps to be examined and securely locked by a duly authorised person before use.[ citation needed ]
Even when new and clean, illumination from the safety lamps was very poor, [23] and the problem was not fully resolved until electric lamps became widely available in the late 19th century. [24]
A modern-day equivalent of the Davy lamp has been used in the Olympic flame torch relays. It was used in the relays for the Sydney, Athens, Turin, Beijing, Vancouver and Singapore Youth Olympic Games. It was also used for the Special Olympics Shanghai, Pan American and Central African games and for the London 2012 Summer Olympics relay. [25]
Lamps are still made in Eccles, Greater Manchester; [26] in Aberdare, South Wales; [27] and in Kolkata, India. [28]
A replica of a Davy lamp is located in front of the ticket office at the Stadium of Light (Sunderland AFC) which is built on a former coal mine.
In 2015, the bicentenary of Davy's invention, the former Bersham Colliery, in Wrexham, Wales, now a mining museum, hosted an event for members of the public to bring in their Davy lamps for identification. [29] The National Mining Museum Scotland at Newtongrange, Scotland, also celebrated the 200th anniversary of the invention. [30] In 2016, the Royal Institution of Great Britain, where the Davy lamp prototype is displayed, decided to have the invention 3D scanned, reverse engineered and presented to the museum visitors in a more accessible digital format via a virtual reality cabinet. At first sight it appears to be a traditional display cabinet but has a touch screen with various options for visitors to view and reference the virtual exhibits inside. [31]
George Stephenson was an English civil engineer and mechanical engineer during the Industrial Revolution. Renowned as the "Father of Railways", Stephenson was considered by the Victorians as a great example of diligent application and thirst for improvement. His chosen rail gauge, sometimes called "Stephenson gauge", was the basis for the 4-foot-8+1⁄2-inch (1.435 m) standard gauge used by most of the world's railways.
Firedamp is any flammable gas found in coal mines, typically coalbed methane. It is particularly found in areas where the coal is bituminous. The gas accumulates in pockets in the coal and adjacent strata and when they are penetrated the release can trigger explosions. Historically, if such a pocket was highly pressurized, it was termed a "bag of foulness".
The Blantyre mining disaster, which happened on the morning of 22 October 1877, in Blantyre, Scotland, was Scotland's worst ever mining accident. Pits No. 2 and No. 3 of William Dixon's Blantyre Colliery were the site of an explosion which killed 207 miners, possibly more, with the youngest being a boy of 11. It was known that firedamp was present in the pit and it is likely that this was ignited by a naked flame. The accident left 92 widows and 250 fatherless children.
Trimdon Grange is a village in County Durham, in England. It is situated ten miles to the west of Hartlepool, and a short distance to the north of Trimdon.
The Geordie lamp was a safety lamp for use in flammable atmospheres, invented by George Stephenson in 1815 as a miner's lamp to prevent explosions due to firedamp in coal mines.
A safety lamp is any of several types of lamp that provides illumination in places such as coal mines where the air may carry coal dust or a build-up of inflammable gases, which may explode if ignited, possibly by an electric spark. Until the development of effective electric lamps in the early 1900s, miners used flame lamps to provide illumination. Open flame lamps could ignite flammable gases which collected in mines, causing explosions; safety lamps were developed to enclose the flame to prevent it from igniting the explosive gases. Flame safety lamps have been replaced for lighting in mining with sealed explosion-proof electric lights, but continue to be used to detect gases.
William Reid Clanny FRSE was an Irish physician and inventor of a safety lamp.
The Oaks explosion, which happened at a coal mine in West Riding of Yorkshire on 12 December 1866, remains the worst mining disaster in England. A series of explosions caused by firedamp ripped through the underground workings at the Oaks Colliery at Hoyle Mill near Stairfoot in Barnsley killing 361 miners and rescuers. It was the worst mining disaster in the United Kingdom until the 1913 Senghenydd explosion in Wales.
The Felling Colliery in Britain, suffered four disasters in the 19th century, in 1812, 1813, 1821 and 1847. By far the worst of the four was the 1812 disaster which claimed 92 lives on 25 May 1812. The loss of life in the 1812 disaster was one of the motivators for the development of miners' safety lamps such as the Geordie lamp and the Davy lamp.
The Gresford disaster occurred on 22 September 1934 at Gresford Colliery, near Wrexham, when an explosion and underground fire killed 261 men. Gresford is one of Britain's worst coal mining disasters: a controversial inquiry into the disaster did not conclusively identify a cause, though evidence suggested that failures in safety procedures and poor mine management were contributory factors. Further public controversy was caused by the decision to seal the colliery's damaged sections permanently, meaning that the bodies of only 8 of the miners were ever recovered. 2 of the 3 rescue men who died were brought out leaving the 3rd body in situ until recovery operations began the following year.
Clifton Hall Colliery was one of two coal mines in Clifton on the Manchester Coalfield, historically in Lancashire which was incorporated into the City of Salford in Greater Manchester, England in 1974. Clifton Hall was notorious for an explosion in 1885 which killed around 178 men and boys.
The Elsecar Collieries were the coal mines sunk in and around Elsecar, a small village to the south of Barnsley in what is now South Yorkshire, but was traditionally in the West Riding of Yorkshire.
A mining lamp is a lamp, developed for the rigid necessities of underground mining operations. Most often it is worn on a hard hat in the form of a headlamp.
The West Stanley Pit disasters refers to two explosions at the West Stanley colliery. West Stanley colliery was a coal mine near Stanley. It opened in 1832 and closed in 1936. Over the years several seams were worked through four shafts: Kettledrum pit, Lamp pit, Mary pit and New pit. In 1882 an underground explosion killed 13 men. In 1909 another explosion took place, killing 168 men. Twenty-nine men survived the disaster.
The Bedford Colliery disaster occurred on Friday 13 August 1886 when an explosion of firedamp caused the death of 38 miners at Bedford No.2 Pit, at Bedford, Leigh in what then was Lancashire. The colliery, sunk in 1884 and known to be a "fiery pit", was owned by John Speakman.
This is a partial glossary of coal mining terminology commonly used in the coalfields of the United Kingdom. Some words were in use throughout the coalfields, some are historic and some are local to the different British coalfields.
The Lundhill Colliery explosion was a coal mining accident which took place on 19 February 1857 in Wombwell, Yorkshire, UK in which 189 men and boys aged between 10 and 59 died. It is one of the biggest industrial disasters in the country's history and it was caused by a firedamp explosion. It was the first disaster to appear on the front page of the Illustrated London News.
The Cymmer Colliery explosion occurred in the early morning of 15 July 1856 at the Old Pit mine of the Cymmer Colliery near Porth, Wales, operated by George Insole & Son. The underground gas explosion resulted in a "sacrifice of human life to an extent unparalleled in the history of coal mining of this country" in which 114 men and boys were killed. Thirty-five widows, ninety-two children, and other dependent relatives were left with no immediate means of support.
The 1923 Bellbird Mining Disaster took place on 1 September 1923 when there was a fire at Hetton-Bellbird coal mine, known locally as the Bellbird Colliery or mine. The coal mine was located near the village of Bellbird, which is itself three miles southwest of Cessnock in the Northern coalfields of New South Wales, Australia. The accident occurred in the No. 1 Workings of the mine and resulted in the deaths of 21 miners and their horses. At the time of the disaster the mine employed 538 people including 369 who worked underground.
On 10 April 1824 an explosion occurred in the Saint-Louis coal mine in Champagney, France. The explosion, called the first disaster at the Saint-Louis coal mine, was the first firedamp explosion in the Ronchamp and Champagney coalfields (Haute-Saône) and one of the first in France. It was also one of the deadliest in the history of the Ronchamp coal mines, killing twenty and injuring sixteen. The disaster had a profound impact on the local population and national opinion, calling into question the safety of firedamp mines and the conditions of ventilation.
This article incorporates public domain material from websites or documents of the Library of Congress .We're not especially interested in valuing them, most are only worth about £50 or £60, but some of the rarest and oldest examples can sell for over £500.
