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 be seen ; but solid rocks and their surfaces are buried out of sight in low lands.

Accordingly the districts chiefly studied for glaciation were mountain-tracts.

1st. The coasts, loughs, and mountains about Dundalk, Newry, the Mourne Mountains, hills in Down, Antrim, and Londonderry, as far as Fairhead in the N.E.

2nd. The mountains and sea-loughs in Cork and Kerry in the S.W.

3rd. Donegal, Sligo, Mayo, and Connemara, in the north and west.

4th. The coast was seen from a yacht, and from a steamer which visited the Lights, from Valentia, by Cape Clear and Dublin, round to Malin Head and Instra Hull.

5th. Points were also looked at in central districts about Dublin, Kildare, and Gal way, Armagh, Omagh, Dungannon, Enniskillen, &c.

6th. Railway-cuttings and roadsides were watched from trains and cars ; and every likely spot that could be reached was examined for ice-marks everywhere.

Where ice hardly exists it is necessary to consider the ways of glaciers and icebergs, and their work of grinding rocks and carrying the debris. I have tried to apply knowledge gained in rambling about the world during many years to rocks in Ireland.

In studying Irish " tool-marks and chips " I tried to assign them to natural engines, like those which I have seen shaping the earth's surface in the Alps, in Scandinavia, in Iceland, and in America, afloat and ashore.

XI. Slieve Liag. — I have said above that I attribute most of the rock forms in Ireland to glacial and to marine action. In Donegal, to the north of the bay near Carrick, is a peninsula of high ground jutting out into the sea, and making the northern horn of the bay. The end of it is a high mountain called Slieve Liag (stone or pebble hill) ; it is nearly 2000 feet high. Seen from near Beinn Gulban in Sligo on the other side of the bay, or from the Carrick Hotel at tbe foot of the mountain, it looks like any other Irish mountain with steep undulating sides. On the north the hill-side is covered with drift. From the head of " Glen river" and from all the high grounds to the east, down all the hollows which now contain rivers, at some late time, a great sheet of glacier-ice slid and flowed towards this tall hill, which split the flood, turned it aside, and shunted part of it out to sea through Teelin Harbour, S.W.

There can be no question about this part of the record. Glacial striae are plain and perfect in quarries and gravel-pits, on rocks of many kinds, on veins of glassy white quartz, on pudding-stone, which is like a rude pavement of rolled stones ; on hill-tops and in river-bottoms. I have rubbings of them.

The sheet of ice certainly travelled some twelve or fourteen miles downhill, some 1500 feet ; and then some of it was forced up a steep incline. At the preventive station at the mouth of Teelin Harbour it went over the hill some three or four hundred feet high