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2. He specified the occurrence of thick beds of detritus, consist- 
ing of clay, gravel, and sand, along the hills between Stratherrick 
and Strathspey, at levels of from 2000 to 2500 ft. above the sea, 
— heights far greater than the sites of the barriers of the old 
Lochaber lakes. 
3. He next indicated on a map the probable sites of the barriers 
by which the lakes of Gflen Roy and Glen Spean had been respec- 
tively confined, till the barriers were broken down, and gave 
reasons for fixing on these sites. 
4. While in his last Memoir he had attributed the breaking 
down of the barriers to the agency of the rivers discharging from 
the lakes, and also of streams flowing upon the barriers from the 
adjoining mountains, he now added another probable cause of 
injury, to the barriers at the mouths of Glen Spean and Glen Glusy 
in the agency of the sea, there being probable evidence that when 
these barriers existed, the sea was standing at a level of about 500 
or 600 feet higher than at present ; and that the blockages of 
these two glens were so near the sea, when at that height, as to 
form sea-cliffs. 
He explained that this evidence consisted, first, in the occurrence 
of sea shells, said to have been found at two places outside the 
Glen Spean barrier, in beds of clay from 200 to 500 feet above the 
sea, by persons whose trusworthiness he had ascertained ; and, 
second , in the existence of a series of terraces, in the district about 
Spean Bridge, from 400 to 500 feet above the sea, which he con- 
sidered to be marine. 
5. Mr Milne Home then adverted to the grounds on which the 
glacier theory rested, and stated that by another visit made 
last autumn to Corry N’Eoin and Glen Treig, the only two 
valleys, where a glacier is supposed to have existed, when Glens 
Spean and Roy were occupied by lakes, he had discovered that 
these valleys, instead of being then filled with ice, must have been 
occupied by water, viz., the water of the Glen Spean Lake ; inas- 
much as there are beach lines round the whole of L oc Treig, and 
also at the mouth of Corry N’Eoin. 
6. Referring to what had been called the Moraines of the 
alleged Treig glacier — viz., at Murlaggan, and in the district be- 
tween the Rough Burn and Fersit, — he said that at Murlaggan 
