ground stream at the various points was made many years ago, * and has been verified of late years by the observation that the working of the Coal pithole Mine caused the water of Russett Well to become turbid. A portion of the water is derived from the limestone hills a little further south. On Eldon Hill there is a great open chasm in the limestone, which was explored in 1771 by J. Lloyd.† The chasm was clear to a total depth of about 87 yards, opening at the bottom into a large chamber. A natural shaft, at that time choked with stones, extended a great depth further, and communicated with a water-course. "It is observed by the country-people in the neighbourhood, that there is a large quantity of grit stone grows in the earth near Elden Hole, but none near Castleton; and yet, on high floods, the river at Castleton washes great quantities of that very grit stone out of the mouth of Castleton Cavern" (op. cit. p. 258). This grit stone will be subsequently described (p. 103). The common report also that a goose, which fell down Eldon Hole, emerged at Castleton, is referred to in this paper.

An equally extensive system of underground drainage occurs near Eyam. There also the swallows occur at the boundary of the Yoredale Shale, the largest of them, a great open chasm on the intersection of the Cross-low and the Black Hole Veins, being about half a mile east of Foolow. The water, which enters this and the neighbouring swallows runs east by Eyam to the valley of the Derwent by way of Middleton Dale. A part of this water-course was explored many years ago, as described by Short.‡

The circulation of underground water has been greatly changed in the last 150 years by the driving of the long soughs or water-levels, presently to be described.

In addition to the water-courses, such as the above, great open spaces have frequently been found in the veins. The cavern intersected by the Speedwell Level (p. 129) is a good example. Others have been found in the. Golconda Mine, near Brassington, and in other places.

The so-called High Tor Cavern is well worth a visit. § It is a fissure (probably a joint which has been enlarged by water) about 600 feet long, from two to seven feet wide, and 150 feet deep, down to the lowest point of the artificial pathway along the bottom, to make which the deeper parts were filled up. It runs nearly parallel to the steep westerly face of the High Tor, and gives us a clue as to how this cliff, thought in the old days of cataclysmal geology to be the face of a fault, may have been produced. In the sketch-diagram given in Fig. 26 the cliff AB which bounds the valley coincides exactly with the line produced of the fissure of the High Tor Cavern, BE. And here surely we see before us cause and effect. Such fissures are common in the limestone, and, by furnishing a line along which the rock, when undermined by the river or underground streams, breaks off most readily, determine the steep cliffs which so often bound these limestone valleys. Such a fissure was doubtless the cause of the cliff of the High Tor, CD, which at one time may have reached farther to the north than it now does, the recess ABC being then filled with a solid mass of limestone up to the

*It is alluded to by Bray in his Sketch of a Tour into shire, 1783, p. 198.

† An Account of Elden Hole in Derbyshire, by J. Lloyd.

p. 250.

Derbyshire and York

Phil. Trans., vol. lxi.,

Access was gained to it

The History of the Mineral Waters, &c., 1734, p. 94. by Carl's Wark, a cave in Middleton Dale, two thirds of a mile west of Stoney Middleton.

§ This note, and Figure 26, of which it is descriptive, are taken from the previous edition of this Memoir.

top of the cliff. After a while, however, the river began to attack this mass of rock too, and worked its way back to the second fissure, of which the High Tor Cavern is now the only remaining part, so giving rise to the cliff AB. There the process ceased; but if the river now retains, or should it ever recover, its power of destruction, the mass BCDE will in time go too, and what is now the eastern face of the High Tor Cavern will become the boundary-cliff of the valley in the place of the precipice of the High Tor.

Fig. 26.

Diagram Sketch of part of the Valley of the Derwent, Matlock.

Bones of Extinct Animals, &c.-We may here notice the discovery of elephant bones in a cavern in the Mountain Limestone at Waterhouses,* a hamlet on the road from Ashbourn to Leek, about seven miles from Ashbourn.

The discovery was made by Mr. William Brockbank, of Manchester, and described by him in a paper read before the Literary and Philosophical Society of that city, December 13th, 1864, from which the following extracts are taken. "A large number of bones were submitted to the society, all of which were considered to be those of the Elephas primigenius, among which were one humerus nearly complete and part of the second; parts of the pelvis and scapula; one ulna; several carpal and metacarpal bones; the head of the tibia; several fragments of tusks; and two fine fragments of teeth, showing very clearly the peculiar narrow transverse plates and ridges of the

*In Map 72 N.E.

dentine and enamel, by which the teeth of this elephant are distinguished. . . . At the furthest point of the cavern reached were discovered a humerus in the socket of the scapula, with the head of another humerus resting upon it at the other end, and two cervical vertebræ were found near the scapula. These were the only bones found in their relative position. Large numbers of ivory flakes were found, which proved to be the remains of teeth, and one large fragment of a tooth was obtained which was decomposing into these flakes." In the discussion on this paper Mr. Binney mentioned that only two other cases had come under his notice of elephant remains in Derbyshire. One is mentioned by White Watson, on p. 58 of his Delineation of the Strata of Derbyshire, in a cavern broken into while sinking a lead mine "at Balleye, within two miles of Wirksworth." And the other is a portion of the tusk of an elephant found by Mr. James Meadows in a limestone-fissure at Doveholes, between Buxton and Chapel-en-le-Frith, and presented by him to the Manchester Geological Society.

The discovery was mentioned to one of the authors of this Memoir by Mr. T. Wardle of Leek, and they visited the spot together three days after Mr. Brockbank, when the sketch in Fig. 27 and the following notes were made.

By aneroid measurement we made out the ground to be about 760 feet above the sea, and found the quarry to be in the upper beds of the limestone. The junction of this formation and the overlying Yoredale shales is seen in the river Hamps, at the turnpike-road, the beds dipping S.S.W. at 40°. The dip continues in the same direction, sometimes at a higher and sometimes at a lower angle, till we reach the quarry where the bones were found; here the beds rear up at angles of from 70° to 80°. The limestone is mostly in layers about two or three feet thick, with a few more massive beds. From the sketch it will be seen that a face of the quarry, running nearly at right angles to the strike, has cut across a narrow tunnel in the rock filled up in part by loose limestone-blocks; among these the bones were found. The roof of this tunnel was about 12 or 15 feet below the surface; its sides were formed by two planes of bedding about five feet apart; its bottom we did not see, but the quarrymen said that the heap of débris below the opening rested on solid rock; this would make the height about 15 feet. At the top of the tunnel was an open space, about big enough for a man to crawl through; Mr. Wardle stated that it ran on for a little way, and was closed at the end by a wall of rock, covered with stalagmite. Below this open space the tunnel was filled up with a tumbled mass of angular blocks of limestone, often covered with stalagmite ("waterspar" of the quarrymen), mixed with reddish clay. We also found three well-rounded quartz pebbles. The more perfect bones had been carried away before our visit, but we found and saw a basketful of broken bits of bone, mostly small and waterworn. We thought there could be no doubt that this had been an old underground watercourse; whether the opening to the surface has been quarried away, or whether it is yet to be found, we cannot say.

Several other instances have since occurred of the bones of large animals having been discovered. A tooth of Rhinoceros tichorhinus was found at the entrance to the Peak Cavern in 1878.* In a cave near Matlock, broken up in the course of some quarrying operations, bones of Rhinoceros tichorhinus, Cave Hyæna, Bear, Reindeer

*Rooke Pennington, Trans. Geol. Soc., Manchester, vol. xv., p. 51, 1878.

(abundant), Fox, Red-deer, and Bison (rare) were discovered.* In Harth Dale, or Gelly Dale, remains of Rhinoceros, Bison priscus (Aurochs), and the Mammoth have been observed.†

At Windy Knoll, near Castleton, a remarkable accumulation of bones of Bison and Reindeer has been investigated by Mr. Rooke Pennington and Prof. Boyd Dawkins. The bones were first noticed in the quarry in a fissure, which, on being followed up, was found to communicate with a basin in the limestone, containing a vast number of bones of Bison and Reindeer, with some of the Grisly Bear, Wolf, Fox, Hare, Rabbit, and Water-mole. The spot is believed to have been a drinking place used by herds of Reindeer and Bison during their migrations to and from the plains of Cheshire. The large numbers of young of both animals, that were found, have led to speculations as to the time of year at which the droves were in the habit of passing.‡

Flint Implement.-In concluding this chapter, we may note that a flint flake was picked up by the late Mr. Richard Gibbs, fossil-collector to the Survey, beside the Wheel Stones, on Derwent Edge (QuarterSheet, 81 N.E.). It is now in the Jermyn Street Museum.§

*Law, Trans. Geo. Soc. Manchester, vol. xv., p. 52.

† Rooke Pennington, Quart. Journ. Geol. Soc., vol. xxxi., p. 241, 1875. Quart. Journ. Geol. Soc., vol. xxxi., p. 246, and vol. xxxiii., p. 724, 1877, and Proc. Lit. and Phil. Soc., Manchester, vol. xiv., p. 1, 1875. See also Plant. Trans. Geol. Soc., Manchester, vol. xiii., p. 117, 1874. Ibid., p. 151 (Aitken).

§ For an account of the numerous implements, &c. found in, or near, the barrows of Derbyshire, see Ancient Stone Implements, Weapons, and Ornaments of Great Britain, by John Evans. 8vo. London, 1872.

CHAPTER IX.

MISCELLANEOUS.

We propose to give in this chapter a summary of the more important of our observations, and to notice a few matters that do not fall under any of the former headings.

Mountain Limestone.-The facts that have incidentally come under our notice respecting this formation are neither numerous nor well con nected, but they tend to overthrow the formal subdivision of the old geologists, Farey, Whitehurst, Watson, and others. According to these observers there are three beds of toadstone, spreading without break over the whole district, and dividing the limestone into four portions, called the first, second, third, and fourth limestones. There would be nothing strange in beds of lava or volcanic ash being very irregular in their occurrence, and the sections in Fig. 3 (p. 26) seem to show that, perhaps with one exception, toadstones are found at different spots on very different horizons, and are of limited horizontal range. Beside the three regular beds the authors mentioned admitted the existence of "chance" toadstones, that is toadstones of local and irregular occurrence; but it seems likely that all the toadstones partake more or less of this character. These authors also speak of the several limestones as if they each bore some distinctive stamp which enabled the observer to recognise them by character, independently of relative position. With the exception of the upper cherty beds our experience does not tend to confirm this view. Indeed the attempt to identify beds far apart by mineral character alone has been a fruitful source of error, not only here, but also among the gritstones and other parts of the Carboniferous rocks; for instance, the Kinder Scout Grit of the Peak and the Chatsworth Grit were long, and very naturally, looked upon as belonging to the same bed, because each was the lowest coarse grit in its own neighbourhood. The fact that such shrewd observers have fallen into these mistakes shows that for such details as these nothing but careful mapping of the whole of the country can be a safe guide, and proves the danger of the old-fashioned method of taking a section here and a section there, and guessing at the probable identities of the beds.

The Upper Carboniferous Rocks. The following Comparative Sections (Fig. 28) show the correlation of the various sub-divisions of the Yoredale Rocks and the Millstone Grit, and also bring out clearly the rapid thickening of the beds towards the north. The districts represented are as follows:

I. Section west of Sheffield.

II. To the north-east of Eyam.
III. Chatsworth and neighbourhood.
IV. Ashover and neighbourhood.
V. Crich and Wirksworth.

Yoredale Rocks-Beds which may be the equivalents of the Yoredale Sandstones of North Staffordshire, but which perhaps ought to be included in the Shale Grit, are found in Edale and about Bamford. Southwards from the last place the Shale Grit seems, with one or two very doubtful exceptions, to be immediately underlaid by the shales and