Safety Lamps
Mining of any kind has always been a risky undertaking. There’s the possibility of cave ins and the enormous difficulty in rescuing miners trapped underground. In addition to these not inconsiderable dangers, coal mining carries an additional risk – that of firedamp.
Firedamp is the name given to various types of flammable gases found in coal mines, the main ingredient being methane. Other flammable gases found in the unique atmosphere of a coal mine include blackdamp, whitedamp, stinkdamp, and afterdamp. These gases are a by-product of the coal formation. When the gas has built up above its explosion point and then contacts a heat source (such as a flame) – it explodes. Firedamp is particularly found in mines containing bituminous coal.
The problem was that in the underground darkness, miners needed lamps to work, and initially the only light available was that of a naked flame. Without warning an explosion could occur, killing the mine workers outright if they were fortunate – if they were not, they could be trapped beneath rubble to slowly suffocate. Safety lamps were needed, and they had to be something other than a naked flame so that miners could work in safety.
It seems that digging deep into mines for coal (rather than accessing coal that lay near the ground’s surface via bell pits) first started in the UK in the late 1500s. Known as deep shaft mining, the demand was partly created, and partly supplied by, the Industrial Revolution. It was common in early years for women and children to be employed in mines as they were paid much less than the men. This practice was abolished by law in 1842.
By this time, the need to create a genuinely safe safety lamp was imperative. Methods for testing whether a mine contained firedamp were primitive, to say the least – a mine worker known as the Fireman, wearing a well dampened wool or leather hooded cloak, would edge through tunnels holding a candle on the end of a stick. If the tip of the flame changed colour to bluish grey, stretching out into a deep blue, it indicated the presence of firedamp. The fireman would, if he was fortunate enough, have detected an amount of gas small enough to still have time to retreat. Arrangements could then be made to ventilate the area. In the event of the fireman setting off an explosion, it was hoped that his wet clothing would at least prevent him from being badly burned.
Early attempts at safety lamps ranged from the bizarre (using dried fish skins which produced phosphorescence) to positively dangerous – spinning a steel disk with a crank and holding a flint against the disk to produce a shower of sparks. Created in 1730, it was known as a Spedding Steel Mill Lamp, and it was incorrectly assumed that the sparks produced would be too weak to ignite firedamp. A few explosions later and it was realised that a better option was needed. Work began in earnest on an efficient safety lamp.
