ANNUAL OF SCIENTIFIC DISCOVERY. 



of cannel having been ascribed to a peculiar and highly resinous vegetation, 

 affected by the agency of heat. This theory being unsatisfactory, Dr. New- 

 berry gave the subject especial attention in his investigations of the Geologi- 

 cal Phenomena of the Ohio System of the Alleghany Coal Field. His observ- 

 ations upon the cannel coal beds of Ohio, the changes they exhibit in going 

 from one front of outcrop to another, their physical and chemical characters, 

 &c., have resulted in giving him the conviction that the peculiar characters 

 presented by beds of cannel coal are due to their deposition in ivater, and the 

 commingling with macerated and dissolved vegetable tissue, which for the most 

 part compose them, and a considerable portion of animal matter. 1st. Cannel 

 coal always exhibits a tendency to assume the foliated structure of slates and 

 shells a structure which it must have derived from aqueous deposition. It 

 often is found shading into bituminous shale into which it is converted 

 simply by accessions of earthy matter. Bituminous shale and cannel coal 

 may therefore be considered the same substance in different degrees of purity 

 that is, consolidated ligneous mud, deposited from aqueous suspension with 

 different admixtures of carbonaceous matter; this carbonaceous matter; in 

 bituminous shales, as in cannel coal, exhibiting a preponderance of volatile 

 matter over fixed carbon, and the gas furnished by it contains a larger pro- 

 portion of the more volatile hydro-carbon, and possesses a higher illuminating 

 power than that derived from ordinary bituminous coal. The chemical com- 

 position of cannel coal, so rich in volatile ingredients, is such as would natu- 

 rally follow the decomposition of vegetable matter while constantly submerged. 

 What we call the decay of plants after the loss of their vegetable life is in fact 

 a combustion an oxidation of their hydrogen to form water of their carbon, 

 to form carbonic acid. Under water these changes go on still more slowly, 

 and a larger portion of the vegetable tissue becomes bitumenized. In such 

 circumstances bitumenization is the oxidation of the carbon and escape of 

 carbonic acid with the combination and removal of a portion of the alkaline 

 phosphates and carbonates, &c.. which go to form the loss the union of hydro- 

 gen with the carbon to form carburetted hydrogen and other hydro-carbons 

 a portion of which are given off and part combine mechanically or chemi- 

 cally with the oxygen, a portion of the alkalies and the earthy matter to 

 form an almost indestructible mass, destined to serve man for the generation 

 of heat, and which we call coal. It is evident that the more ready the access 

 of oxygen to the carbonaceous matter during the process of bitumenization, 

 the larger the proportion of the products of the process will be those of com- 

 bustion ; and the more perfectly the oxygen is excluded, the larger proportion 

 of the more volatile and combustible constituents of the wood will be re- 

 tained. Of the conservative influence of water and vegetable matter we 

 have ample evidence, not only in the almost incalculable durability of wood 

 when constantly submerged, but in coal itself. In all beds of coal except 

 those where the process of volatilization is complete, in plumbago, and per- 

 fectly gasless anthracites, the work of decomposition is constantly going on, 

 and water is to this, as to ordinary -combustion, an extinguisher. In this 

 country coal is commonly mined from the outcrop, in some hill side, where it 

 is not covered by standing water ; in such circumstances a progressive change 



