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TRIALS FOR COAL UNDER THE BASALT OF THE HOAR EDGE. 



yards, trials were commenced to determine the second object, viz., the existence of coal 

 measures under the basalt of the Hoar Edge, or in other words whether the basalt on 

 the north-western side of the dyke had there flowed over the coal as in Cornbrook. 

 A first shaft was sunk close to the north-western flank of the Hoar Edge, and after 

 passing through a few feet of fallen Jewstone, it traversed a suite of promising coal 

 measures, consisting of shaly sandstone, clunch, bind, clod, ironstone, and grits both 

 coarse and fine, with many impressions of plants and a small seam of impure coal or 

 " flam," all of which, though so near to the basaltic edge, were little disturbed. It was, 

 therefore, probable that the contiguous sheet of basalt had not been erupted very near 

 to this escarpment of the Hoar Edge, which agreeing with the phenomena observed 

 along the Jewstone dyke, still more confirmed the hypothesis, that the dyke alone had 

 been the chief channel of eruption, and if so that the space of nearly half a mile which 

 is interposed between the north-western side of the dyke, and the Hoar Edge (see Map 

 and PI. 30. fig. 8.), might be a productive coal-field, like that of Cornbrook, simply co- 

 vered by a sheet of basalt. This first trial, though thus promising, was abandoned 1 on 

 account of a great influx of water, and a second was commenced with an adequate en- 

 gine a little further removed from the basalt. The shaft, after passing through ninety- 

 one yards of overlying measures, including a sandstone rock twenty-one yards thick, 

 with the other strata, consisting of "horse-flesh" measures, bind, balls of ironstone, 

 coal smut, &c, reached a four-foot coal of good quality. As the object of Mr. Lewis 

 was to prove the full extent and value of his mining ground, he continued to sink 

 beneath this bed of coal in hopes of finding other seams. After penetrating, however, 

 to the depth of thirty-four yards below the coal, through rocky and grey-coloured clunch 

 with coal plants, and after passing the bottom sandstone rock, instead of discovering 

 another coal seam, he unexpectedly met with a singular mass of a dingy red colour and 

 without appearance of bedding. Having driven downwards in this mass to the further 

 depth of twenty-two yards, without being able to discover the least change in its mineral 

 character, he made a horizontal drift aross it to the west, not far beneath its summit. 

 In a few yards the work passed from the red rock into the coarse grit and con- 

 glomerate of the millstone grit, the edges of the beds of which were turned up at the 

 point of contact with the red mass. (See PI. 30. fig. 8.) Mr. Lewis thus saw that he 

 had reached the very bottom of the coal-field, but the nature of the red rock was still 

 a matter of surprise to him. He next drove a gallery towards the opposite side, and 

 rather in an ascending direction, i. e., towards the productive coal-field; and in an equally 

 short distance the opposite extremity of the red substance was reached and the work- 

 men were again in coal measures. At this period I happened to visit the works, and 

 the following data appeared to me to be well established. 1st. As this red rock when 

 first exposed was but little broader than the mouth of the shaft, and at the depth of 



1 It was the intention of Mr. Lewis, when I last visited this county, to proceed again with this shaft, and to 

 connect it with his work, when by his new operation at a lower level he shall have drained the ground. 



