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A few days since an eminent Geologist remarked to me—"Twenty years ago I thought I knew all about the drift; now I am doubtful if I know anything certain about it." In fact, the more those surface deposits which we assign to the glacial period are studied, the more difficult does the problem of their precise origin become. In Leicestershire we find the oldest glacial deposits to be beds of sand and gravel, which are seen at certain points to he overlaid by a stiff, clayey mass, full of stones of all sorts and sizes, to which the name of the "Great Chalky Boulder Clay" has been assigned, from the number of fragments of chalk which it, contains. This arrangement holds good elsewhere, but both on the east coast, (Lincolnshire, &c.,) and the west coast, (Lancashire, &c.,) the sandy, gravelly deposits are underlain by clayey deposit, or Lower Boulder Clay, which is absent in Leicestershire.

In the Upper Boulder Clay of this county there are many fine masses or erratic blocks, some of which are referrible to the Mountain Limestone, others to the Millstone Grit or carboniferous sandstones, still others to the Lower Oolite, but the finest masses are decidedly those from Charnwood Forest, as we might expect from its immediate proximity. Of rocks foreign to England no authenticated instance has ever occurred.

Of the Charnwood Rocks none are more readily recognisable than those of Mountsorrel, under which name I include the entire igneous mass which covers about one square mile of surface in the vicinity of the famous quarries. The stone is a hornblendic granite, finely crystallised, and of a pink or grey hue according to the tint of the felspar. Erratic masses of this rock occur at intervals along a definite line on the east side of the Soar Valley, a line which is marked by the occurrence of soma very fine blocks.

Some of these boulders have attained to the dignity of as mention in the pages of the historian, and among these is the mass whose disinterment I am about to describe.

It is situated in a field 2¾ miles north-east of Leicester, and on the north side of the road from Humberstone to Thurmaston. Here it lies nearly on the top of the low ridge of Rhactic Beds and Lower Lias, which forms the eastern boundary of the Soar Valley. The boulder clay in which it is embedded rests on the Lower Liss, the mid-glacial deposits being absent. Mountsorrel hears north-west, and is on the west side of the Soar Valley, which the boulder has consequently crossed. The spot where it now lies is about 260ft. above the level of the sea.

In Nichels' History of Leicestershire, (Vol. III., p. 981,) this stone is referred to by the Rev. Mr. Woodcock, who says that there is a tradition that a house, or cell, or nunnery, having some underground connection with the Abbey of St. Mary de Pratis, in full view of which it would stand, was ounce situated here. The block was called "Hellstone," or "Holstone," and the field "Hoston Field,” a word which seems to be a