4. At Alnwick Hill, near Liberton Church, at an elevation of about 350 feet above the sea, extensive excavations have been made in the boulder clay for the new Edinburgh water-works. The boulders consist chiefly of fragments of rocks, which are known to be in situ situated in districts of the country to the west and north-west. The great majority of the boulders are of hard red sandstone rock, such as occurs at Grange and Merchiston, to the west of Edinburgh, though these places are at a lower level. There are boulders of marine limestone, similar to rocks of that description in Linlithgowshire. There is an immense quantity of blue-coloured greenstones and dark-coloured basalts, and also buff-coloured felspathic rocks. There are some small boulders of pure quartz, which probably hail from the Silurian rocks to the north-west of Callendar and Doune.

Many of the boulders occupy positions, present shapes, and bear marks of some interest.

The largest seen by the Convener were about 7 feet long by 4 feet wide, and 24 thick or deep.

The boulders were all well rounded and smooth, but more particularly so on what had been the upper and the under sides.

Mr Black, the superintendent of the excavations, being aware of the interest attaching to the position of the boulders and the striæ on them, had, with a compass, ascertained that the long-shaped boulders, before being moved, generally were lying in directions varying between W.N.W. and N. W.; that the striæ, when such existed, were almost always parallel with the longer axis of the boulder; and that there were striæ, sometimes only on the upper side, sometimes only on the lower side, sometimes on both sides. In one of the boulders, well rutted on the under side, he had remarked that the ruts were deepest at the east end of the boulder, and that they gradually diminished in depth and numbers towards the west. This feature might be accounted for on the supposition that the boulder, whilst being pushed forward, encountered hard obstacles which produced deep ruts on the boulder when the first

of Glasgow, as suggested by Mr Peach, what was the transporting agent to suit those localities? A glacier moving from west to east by the action of gravity would be hardly conceivable. The levels preclude that agent. A sea current, loaded with floating ice, seems a more probable conjecture.

contact took place, afterwards the boulder would rise over these obstacles, and in consequence the striæ produced by them would diminish in depth.

5. Tynecastle, near Edinburgh.-A basalt boulder, 4 x 4 x 2 feet, was discovered, striated on both upper and under side, but the ruts were much deeper on the under side. The under side ruts had begun to be formed at the east end of boulder, -the striæ on the upper side begun at the west end. This might be accounted for by supposing that the boulder had been pushed towards the east over hard rocks, and that floating ice from the westward had pushed stones over the upper surface. The smallest end of boulder pointed towards west. The sides of the boulder were well rounded.

This boulder lay in a hill of muddy sand containing many pebbles of all kinds, hard and soft, such as quartz, shale, and coal. Height above sea, 200 feet. Ed. Geol. Soc. Tr., vol. ii. p. 347.

PEEBLESSHIRE.

At the east end of the town of Peebles there is a boulder of white quartz, about 3 feet long, 2 feet broad, and with a girth of about 7 feet. It is now built into a wall. Previously to its being thus disposed of, the stone stood from time immemorial in an adjoining low hill, which in consequence had obtained the popular name of the "White Stone Knowe." It is alluded to as a boundary stone in a title deed dated in 1436. Mr Richardson, the Secretary of the Edinburgh Geological Society, who was the first to take public notice of this boulder, says that "the nearest beds of quartz are about 80 miles to the N.W." The boulder on its surface is smoothed and polished. It is, like many other boulders, rudely pointed at one end, whilst the other extremity is more broad and heavy. The height above the sea is 550 feet.-Ed. Geol. Soc. Trans., vol. ii. p. 397.

PERTHSHIRE.

1. Loch Tay.-On the farm of Morenish, situated on the north bank of the lake, and about 2 miles from the village of Killin, there are several boulders worthy of notice.

Figs. 13, 14, 15, Plate II., are intended to show the positions and specialties of these boulders. They were at a height of about 1400 feet above the sea, assuming Loch Tay to be 300 feet.

These boulders had all come from the westward, viz., down the valley, as shown by the way in which they were fixed.

If the question be, whether they were brought by glacier or by floating ice, the answer is, that there is not much evidence either way. It may however be remarked, that if they were pushed forward by a heavy glacier, it is odd that the boulders should not have been carried further down the valley, and that the obstructions on their east side, against which they have stuck, should not have yielded under the pressure of a ponderous glacier. The boulders in figs. 13 and 14 were resting on detritus, and pressing against detritus only on their east sides. The boulders in fig. 15 was pressing against a hard rocky stratum of clay slate on its east side.

In several parts of the hill, smoothed rocks of mica schist occur, with knobs of quartz standing up above the general surface. Being harder than the mass of rock, they had resisted the friction better; these knobs were smoothed, the smooth parts being always on the west sides.

Fig. 16, Plate III., shows a rock with joints. The projecting angles facing the west have been smoothed by some abrading and grinding force.

2. Glen Dochart.-There are many boulders of considerable size, resting on detritus, and chiefly on the south side of the valley.

One near an old toll-bar measured, in so far as above the ground, 13 × 12 × 8 feet, at a height of 630 feet above the sea.

At the small farm-house of Wester Lix, at a height of 660 feet above the sea, there is a flat or terrace, partly rock, partly detritus, on which there are several large well-rounded boulders, two of them a coarse granite, probably from Ben Cruachan.

On ascending the hill towards the south, a boulder, 12 × 9 × 5 feet, was met with, at a height of 1116 feet above the sea. Its longer axis bore E.S., which is also the direction of the axis of the valley in this place. There being no rocky hill near, from which this boulder could have come, it has certainly been brought to the spot where it now lies, by some transporting agent.

At the height of 1250 feet there is a mass of rock on the same side of the valley, and nearer the top of the ridge, which has on it some noteworthy marks. The rock stands out prominently, and forms a nearly vertical cliff, as shown in fig. 17, Plate III. On the side

facing the west, there are horizontal groovings, apparently formed by some force, which, acting on the whole mass, has worn down certain portions more than others, these portions being less compact, and so more capable of abrasion.

Such abrasion might have been effected by a body of water passing from the westward; and more readily, than by the solid ice of a great glacier.

On the top of the ridge forming the south bank of this valley (Glen Dochart), a cairn stands at a height of 1500 feet above the sea. A boulder of considerable size lies on the top of this ridge, on the east side of a projecting knoll. Has the boulder been stranded on what was the lee side of the knoll?

ROSS-SHIRE.

At Auchnasheen (Dingwall and Strome Ferry Railway,) there is a boulder about 15 feet in girth, which stands on a flat of detritus about 610 feet above the sea.

In this district, there are several other detrital flats, in sight of this one, all nearly on the same level. There can be no doubt that these flats have been originally one continuous plateau, which formed a sea-bottom. It has been cut through by several streams, the banks of which, about 18 feet high, show an enormous accumulation of gravel and sand;-sand, below (deposited probably when the water was deep); gravel, above (deposited when the water was shallower and more subject to currents).

The annexed diagram represents a portion of these remarkable flats, -cut through by several streams, the principal of which flows from Loch Rosque, situated to the north of the boulder. The knobs. on the woodcut are intended to represent knolls of gravel or sandremnants of a greater mass of these materials. The boulder is well rounded, and it has evidently come from a distant quarter.

Professor Nicol of Aberdeen has expressed an opinion that the formation of these Auchnasheen terraces is due to the action of a great river flowing from the west. I regret to differ on this point from a geological friend; but I can see no grounds for that opinion. To the east of Auchnasheen, close to the railway, there are several spots of rock evidently rounded by friction-whether by ice or by * Nicol's Geology of Scotland, p. 69.

water, or by both, it is difficult to say. Their height above the sea is about 780 feet. On the hills, on each side of the railway, there are traces of horizontal lines on the detritus, which deserve better observation than could be given from the railway carriage.

NORTHUMBERLAND.

It was intended that only Scotch boulders should be inquired. after by the Committee; but it is not irrelevant to notice a boulder which, though now in England, was probably transported from a Scotch mountain.

In Chillingham Park, the seat of the Earl of Tankerville, near Alnwick, there are several small boulders of granite. The rocks of the immediate neighbourhood are carboniferous sandstones and limestones. The nearest point for granite is the "Big Cheviot," eight miles to the W.N. W., and reaching a height of about 1800 feet above the sea. The largest boulder is 3 feet 2 in length, 2 feet