Trans. N. V. Ac. Set. 160 Apr. 24,. 



groups known as the Lower Helderberg, Clinton and Knox or Calci- 

 ferous. 



The existence and excellence of the iron ores of Southwest Virginia 

 have been known for many years ; but the chief interest of the region 

 now centers in the coal deposits, whose value and accessibility have 

 been ascertained very recently. The coal occurs at three horizons : 



The Coal Measures, 



The Quinnimont Group, 



The New River Group. 

 The area of the Coal Measures in Virginia is comparatively small, 

 probably less than 600 square miles, the greater part of the field being 

 in Kentucky and West Virginia. It occupies portions of Lee, Wise, 

 Russell and Buchanan Counties, lying along the Kentucky border. The 

 most readily accessible part is that in Lee and Wise Counties, and is 

 drained by Powell River, a large stream entering Clinch River near 

 Knoxville, Tennessee. Stone Mountain, a bold ridge of vertical con- 

 glomerate and the southeastern wall of the coal-field, is broken by two 

 gaps, through which the Powell River and its North Fork flow. These 

 can be reached by following the river from Knoxville, or by a shorter, 

 though more difficult, route from Bristol, on the Norfolk and Western 

 Railroad. The latter route has been chosen, and a narrow-gauge rail- 

 way is in course of construction. 



Measurements on the head waters of Powell River, behind the " Big 

 Stone Gap," afforded me a vertical section of nearly 2500 feet of Coal 

 Measures, containing twenty-one coal beds, vdixymg in thickness from 

 four inches to fifteen feet ; but the productive part of the section is 

 confined to the lower 920 feet, the beds higher up being very thin. 

 This section doubtless represents all the Coal Measure groups of Penn- 

 sylvania, but detailed comparisons are impossible for the present, there 

 being no limestones or other fixed horizons to be used for that purpose. 

 Four of the coal beds deserve notice. Two beds of splint are found 

 high up in the productive portion of the section. They are separated by 

 an interval of 70 feet, and are from 3 feet 6 inches to 4 feet thick. Their 

 coal is a hard gray splint, very like that obtained on the Kanawha. 

 Analyses by Mr. A. S. McCreath show that this Powell River splint 

 contains little more than 3 per cent, of ash and less than one-half of 

 one per cent, of sulphur. The Kelly Coal-bed, 215 feet below the lower 

 splint, is from 2 inches to 15 feet thick, but in a large part of the 

 area maintains a thickness of from 5 to 7 feet. The middle bench, 2 

 feet 6 inches thick, is an admirable _^«j coal ,\\)c\& lower bench is a 

 fair splint, while the upper bench is worthless. Mr. McCreath 

 found in the middle bench, .890 per cent, of ash, .771 per cent, of sul- 

 phur, while the volatile matter is 38.850. The Imboden bed is 50 feet 



