228 Geological Society. 



an abrupt hill of the shale, considered to have been also brought up 

 by a fault; and on its northern face commences a broad valley- 

 formed of coal measures, and bounded at its further extremity by 

 another hill of graywacke, likewise thrown up by a fault. Coal is 

 worked on three sides of this hill. The graywacke continues thence 

 for six or seven miles, when the coal sandstone again constitutes 

 the surface for a short distance (2 miles), and, after another interval 

 occupied by graywacke, reappears forming the country around Ra- 

 konitz. 



Section 3. Zebrak to Ginetz. — This section refers to a more 

 southerly part of the district, and traverses a portion of the coal 

 measures situated south of that line of graywacke which extends from 

 Pilsen to Prague, and separates, except at one point, the coal field 

 connected with the two first sections, from the district about to be 

 noticed. At Zebrak, the point just mentioned, the coal measures 

 intersect the graywacke range, in consequence apparently of a fault ; 

 and the section commences at Zebrak in graywacke shale near 

 the junction of the coal measures with the graywacke. These shales 

 extend to Horzowitz, where they are overlaid unconformably by the 

 coal sandstone, which constitutes the surface of the country for 

 about two miles. At that point is a hill, on the summit of which 

 occurs a cherty sandstone considered by Mr. Ansted to be the base 

 of the coal measures and to have been forced up into its present 

 position. The beds dip about 60° S.E., and rest apparently upon 

 a very coarse, hard, red conglomerate, to which succeeds a vast de- 

 velopment of shale, containing occasionally Trilobites. This divi- 

 sion of the graywacke series, is at some distance, covered again by 

 the conglomerate upon a change of dip, and then continues nearly 

 three miles to Ginetz, with the strata moderately inclined to the 

 N.E. At that town a band of limestone occurs reported to be rich 

 in Trilobites. 



Section 4. Przilep to Karlstein. — This section is parallel to the 

 last, and crosses the line of country between Pilsen and Prague. 

 Two or three tolerably thick beds of coal are worked near Przilep 

 and supply Prague with fuel. Fossils also are not deficient. About 

 6 miles towards the north-west, other but inferior beds of coal are 

 wrought ; but towards the east, the coal thins out between lofty pre- 

 cipices of shale, which form a narrow gorge. Pursuing the line of 

 section towards the south-east, the direction of the dip, and at no 

 great distance from Przilep, the coal basin is shut in by the steep 

 face of a hill. At this point, Mr. Ansted believes, that the lower 

 beds of the coal measures are not only brought up, but are bent over 

 the upper, because, though the dip of the strata is to the S.E. or 

 in the direction of the section, yet, on the summit of the hill above 

 mentioned, is exposed an excellent natural surface of chert ; and in 

 a quarry near the top the inclination of the beds is about 25° S.E. 

 or in the regular dip of the coal measures ; and in a narrow valley 

 at the bottom of a somewhat rapid descent, the lowest division of 

 the graywacke is exposed dipping S. or actually overlying the coal 

 measures. This inversion of superposition, Mr. Ansted explains by 



