SKETCH OF THE RISE AND PROGRESS OF THE DISCOVERY AND APPLICATION OF COAL-GAS, AS A SUBSTITUTE FOR PROCURING ARTIFICIAL LIGHT.
To assist the reader in comprehending the nature and object of substituting coal-gas for tallow or oil, for the purpose of obtaining light, it may be proper to touch slightly upon the successive discoveries that have been made as to the decomposition of coal, and the application of its different ingredients. Such a sketch will add to the many examples that occur in the history of science and art, showing the slow progress of mankind in following up known principles, or extracting from acknowledged facts every possible advantage.
In the Philosophical Transactions of the Royal Society, V. XLI. so long ago as the year 1739, is recorded a paper, exhibiting an account of some experiments made by Dr. James Clayton, from which it appears that the inflammable nature of coal-gas was then already known. Dr. Clayton having distilled Newcastle coal, obtained, as products of the process, an aqueous fluid, a black oil, and an inflammable gas, which he caught in bladders, and by pricking these he was enabled to inflame the gas at pleasure.
It is further known, that in the beginning of the last century, Dr. Hales[11] on submitting pit-coal to a chemical examination, found, that during the ignition of this fossil in close vessels, nearly one-third of the coal became volatilized in the form of an inflammable vapour. Hence the discovery of the inflammable nature of coal-gas can no longer be claimed by any person now living.
In the year 1767, the Bishop of Llandaff[12] examined the nature of the vapour and gazeous products evolved during the distillation of pit-coal. This learned philosopher noticed, that the volatile product is not only inflammable as it issues from the distillatory vessel, but that it also retained its inflammability after having been made to pass through water, and suffered to ascend through two high curved tubes. The solid matters obtained by this venerable prelate, were, an aqueous ammoniacal fluid, a tenaceous oil, resembling tar, an ammoniacal liquor, and a spongy coal, or coke.
The first discovery and application of the use of coal-gas for the purpose of illumination is claimed by Mr. Murdoch.