This is an account of the work of Henry Rees Davies, my great-granduncle, on his patented improvements to safety devices on miners’ safety lamps and on his invention of what may have been the world’s first intrinsically safe (sparkless) electrical signaling relay for use in coal mines.
Some years ago I had the unenviable task of winding up the estate of Margaretta, the daughter of Henry Rees Davies, who had died intestate and without issue; that is to say without making a will and having no children.
Here I make a plea to any reader who has not yet made a will, to do so, since, having gone through the above not-to-be–repeated experience, the procedure places much work on the individual and not only does it take an inordinate amount of time to search out the family tree to establish the beneficiaries, and in this case some beneficiaries received one sixty-fourth part of the estate’s value, but every part of the estate has to be converted into cash, that is sold or auctioned with all receipts being well documented and a solicitor has to be appointed who will charge for his services. The months of work that this process entails could easily be avoided by the relatively short time that it takes to make a will. End of plea.
Amongst the estate papers were records, although somewhat incomplete, of the activities of the said Henry Rees Davies, who was a prolific inventor and held patents for improvements in Miners Safety Lamps and for the invention of what may be the first intrinsically safe* electrical signaling relay for use in coal mines.
* An Intrinsically Safe piece of equipment is an electrical device that is incapable of causing an ignition of the prescribed flammable gas, vapour, or dust, regardless of any spark or thermal effect that may occur in normal use, or under any conditions of fault likely to occur in practice.
A Brief Background of Regulation of and Illumination in Mines
Mining for coal has always been one of man's most dangerous activities. However, because of the great benefits that coal and its by-products produce, it has for hundreds of years been an activity that has been developed and the mining practices greatly improved as a result of lessons learned the hard way, which inevitably resulted in the loss of thousands of lives.
Improvements were not always welcomed by the mine owners, especially if they would cost them money to implement and operate, with little or no increase in production, thus profit. However, during the last century, and mainly as a result of the increasing strength of mining unions and the very high loss of life, slow progress was made in improving the lot of the miner.