INVENTORS
The source of illumination varied from basic oil to tallow and wax in the form of candles. Another source was acetylene which was produced by adding water to Calcium Carbide in a pressure vessel and burning the resulting gas via a nozzle.
For details of the various methods of illumination used in mining and other mining equipment, please click on the following link.
Another good web-site is produced by the Canadian Mining Museums at,
At the time, there were a number of different designs that enabled the bonnets and oil wells of miners’ safety lamps to be locked.
Some had a key operated lock whilst others incorporated a device through which the hasp of a “standard” lock could be placed. However, the disadvantage of these types of locking mechanisms was that the locks could be picked or sawn off.
An example of this practice was made public during the enquiry into the following accident.
An accident at Fochriw Colliery which occurred on Tuesday 3 June 1902 at 3.00 a.m. A fall occurred underground which caused the stopping of ventilation that resulted in a build-up of methane gas and subsequent explosion in which 8 men were killed. The rescuers found 2 packets of cigarettes and a key, normally used for the opening of tins of meat, which had been adapted to open a safety lamp which was found nearby with its top off and gauze removed.
Other patented magnetic locking devices were also being manufactured however these seemed adequate until the mines were electrified when the magnetic field generated by electric motors could be used to free the locking mechanism and, as such, Henry Davies’s invention prevented this happening in as much that a very strong magnetic field was required to activate the key and, unlike modern safety lamps which still employ the same principle, the lock was located on the outside of the lamp as opposed to the very integral design of today’s units.
From his sparse notes and diary entries that survive, it is not clear as to when he started work on his inventions. However, an entry in his diary for Monday 3 October 1892 lists the following items to enable him to construct an electromagnet, a coil for testing detonators and an accumulator for
One method of illumination that is not mentioned in the above websites is the Carlyle Spedding device shown opposite. More information on this can be obtained from the following website.
www.mining-memorabilia.co.uk/NakedFlameLamps.htm
www.mining-