1863.1 185 [Lesley. 



two-thirds of a mile." Explorations beyond this line have failed to 

 find it. Its outcrop, four feet ten inches thick, was discovered cross- 

 ing a ravine fifty feet wide at the bottom, and rising on each side 

 with slopes of nearly forty-five degrees. On one of these hillsides at 

 a height of ninety feet, the outcrop showed the same thickness, but 

 at a height of one hundred and eighty-five feet, it was found to be 

 but two feet six inches thick. It is not certain that this diminution 

 is in a vertical direction ; it may be lateral ; for the slope between 

 the ninety and the hundred and eighty-five feet levels is more gra. 

 dual, especially upon the western side. 



In the bottom of the ravine, a vertical shaft was sunk to a depth 

 of thirty-four feet upon the vein, which continued uniformly four 

 feet ten inches thick, the asphaltum being filled in, pure and clean, 

 without the least admixture of earthy or foreign ingredients, between 

 the smooth and almost perfectly vertical walls of yellowish-greenish 

 sandstone, lying in horizontal layers, through which this gash or fault 

 was once no doubt an open fissure, communicating with some reservoir 

 of coal oil, which still, it may be, lies beneath it undisturbed. The 

 most interesting part of the phenomenon for structural geologists is 

 this gash. 



2. The substance which fills this gash-fault in the coal-measures of 

 Northwestern Virginia, resembles the glossiest, fattest caking coals, 

 and has a decidedly prismatic structure; breaks up into pencils, with 

 flat, lustrous faces and sharp edges, but the faces not set at any fixed 

 angles to each other; so that the effect upon the eye is rather that 

 of a fibrous than of a prismatic structure. At the same time there 

 is not the slightest appearance of layers, but the aspect of complete 

 uniformity or homogeneity. Pieces are taken out, it seems, a foot 

 in diameter; and that portion of one of these pieces which I have, 

 shows a plain face on one side, as if it had encountered one of the 

 walls, and is covered with a delicate film of a dead black substance 

 like charcoal dust, which is probably the dust of the vein substance 

 itself. 



"Pieces lying at the surface of the ground are said to yield as much 

 oil as specimens taken out six or eight feet down. By the ordinary 

 dry distillation, the substance is reported to yield as much oil as the 

 Albert coal. By a different process, the first and only trial, at which 

 600 pounds in one charge was used, 44^ gallons of superior oil was 

 obtained. Retorts are now upon the ground." 



By an assay made by Mr. B. S. Lyman, of Philadelphia (the 

 amount of hydrocarbon soluble in benzole being about one-half of the 



