Lord Dundonald, in 1787, whilst distilling coal for the production of tar and oil, noticed the formation of inflammable gas, and even used it for lighting the hall of Culross Abbey.
This first step has led to the synthetical production of the most characteristic substances of essential oils in the laboratory, and the synthetical manufacture of essential oils bade fair to rival in importance the production of tar colours from the hydrocarbons obtained on distilling coal.
Tully and now in use at Truro, in which tar is injected into the incandescent fuel in a water-gas generator and enriches the water gas with methane and other hydrocarbons, the resulting pitch and carbon being filtered off by the column of coke through which the gas passes.
At one end a ruminating tar was still further adorning it with his jack-knife, stooping over and diligently working away at the space between his legs.
It is a light boat, oval in shape, and formed of canvas stretched on a framework of split and interwoven rods, and well-coated with tar and pitch to render it water-tight.
From the tar distillate, the chrysene can be fractionally precipitated, and the fluoranthene can be separated from most of the pyrene by fractional distillation in a partial vacuum.
The following table will give an approximate idea of the proportions which go to each Nitrogen as ammonia cyanogen in gas and combined in tar in coke .
The three isomeric cresols are found in the tar obtained in the destructive distillation of coal, beech-wood and pine.
PAIGNTON, a seaside resort in the Torquay parliamentary division of Devonshire, England, on Tar Bay, 24 m.
Very many attempts have been made to utilize tar for Enrich- the production and enrichment of gas, and to do this meat by two methods may be adopted: tar.