THE TECHNOLOGIST. [May 1, 1865. 



450 THE CANNEL COAL OF FLINTSHIRE. 



Britain. It is still a question sub judice, whether the Boghead coal of 

 Scotland is really a coal or a schale. Courts of law have declared it to 

 be coal, at least commercially, but many eminent scientific men still 

 maintain that it is only a highly- bituminous schale. However this may 

 be, no question of the kind can arise concerning the Leeswood cannel 

 coal, which is in every respect a true cannel, but yielding liquid pro- 

 ducts when distilled as abundant and as good in quality as those 

 obtained from Boghead cannel. One of the principal characters upon 

 which the advocates of the schale doctrine concerning the Boghead 

 mineral rely, is the peculiar nature of the coke or residue left when the 

 mineral is distilled. 



This, like the coke from acknowledged schales, contains a very large 

 percentage of aluminous ash, which renders it totally worthless for 

 fuel ; but the Leeswood cannel coal is free from this defect, and yields, 

 after distillation, a compact coke, which, from one variety of the 

 cannel, is almost unequalled in quality. In 1859-60, this coal was 

 placed in the hands of the late Dr. Fyfe, of Aberdeen, and Mr. Keates, 

 of Loudon, for thorough chemical examination. Lengthened reports 

 were made by these chemists as to the quality of the coal, both as a gas 

 coal and in respect to its oil-producing capabilities ; and these reports 

 were of such a character, that since that period the coal seems to have 

 been gradually more and more highly appreciated. 



The principal characteristic of the Leeswood cannel coal is its 

 extreme bituminousness, to coin a word. A small piece, thrown into 

 a fire, immediately ignites, and burns with a bright white flame, throwing 

 off at the same time an abundance of separated carbon, and when dis- 

 tilled at the gas-making temperature, it yields a large quantity of gas 

 of the highest illuminative power. The seam of cannel, altogether 

 about six feet in thickness, is divided into four strata of coal of different 

 qualities, but all valuable as oil-yielding coals. There are — above, a kind 

 of coal-schale, highly bituminous, and yielding, when distilled at a low 

 temperature, from thirty-two to thirty-five gallons of crude oil per ton ; 

 below that, what is called the smooth cannel, yielding forty to forty- 

 five gallons of crude oil per ton ; and a coke of very peculiar and 

 valuable quality, resembling the charcoal from a very hard wood. 

 Next in the series — what is looked upon as the most valuable of all 

 the strata — the curly coal, so called on account of its remarkable 

 twisted fracture, which yields seventy-five to eighty gallons of oil per 

 ton ; and lastly, what is known as bottom cannel, very similar in 

 character to the smooth cannel above, excepting that the coke is of 

 inferior quality. These four strata make up the entire seam of the 

 cannel, which lies at about two hundred yards below the surface, upon 

 a stratum of good iron-stone, with fire-clay. The discovery of this coal 

 was a fortunate circumstance in relation to the manufacture of these 

 mineral oils. Before this discovery, as we have already stated, the only 

 indigenous substance largely used was the Boghead coal ; and as the 



