126 THE GEOLOGIST. 
the neiglibouring glens. Some of these anomalies indeed assist in 
proving the probability of the hypothesis ; . . . the remainder, yet un- 
accounted for, may perhaps be explained hereafter. . . . One short 
' line ' only is found in the upper valley of Glen Eoy ; yet all the 
sides exhibit a general equality of slope, form, and texture ; nor is any 
side more than another, subject to the action of a visible ^Yasting 
cause. A great deficiency of the whole of the ' lines ' occurs also to- 
wards the bottom of lower Glen Eo}^ and many partial ones in other 
places. Of these, some evidently arise from the rocky nature of the 
margin ; and others may perhaps be the consequence of the coinci- 
dence between the slope of the hill and the slope of the supposed 
shore. But these causes will not account for them all ; nor are there 
sufficient marks of the action of posterior waste to explain them. 
The anomalies of Glen Hoy and Glen Spean in particular . . . seem at 
present to baffle all explanation, and in this unsatisfactory state must 
the argument remain. It were well if there were not further diffi- 
culties to encounter in adopting this hypothesis, but it is necessary 
to enumerate them. ... As the level of the upper Mine' of Glen Eoy 
is higher than those of many valleys which would at present affijrd 
passage to the supposed waters of Glen Eoy'into the sea, it follows 
that water could not now stand at that level unless these apertures 
were obstructed to at least a higher elevation. The determination 
of the position of these imaginary barriers is consequently the next 
point to be considered ; as well as that of their number, since possibly 
two of these openings might be closed by a single obstruction." . . . 
" The uppermost one is of such a height that the water standing at 
that level would now flow out by Loch Spey and Loch Laggan, through 
the valley of the Spey, into the eastern, and by Loch Eil, Loch Shell, 
and Loch Ness into the western sea. The two lower ' lines ' lying 
below the barriers of Loch Spey and Loch Laggan, it would, under 
similar circumstances, find its way through the three latter openings 
only. The condition of the surrounding land must therefore have 
so far diftered at that time from its present state, that various dams 
or barriers must have existed in the course of these openings. . . . The 
conditions of the present barriers existing at the source of Loch Spey 
and to the east of Loch Laggan, are such as to give no reason to ima- 
gine that they have once been higher. . . . By the removal of the sup- 
posed barriers to a point below Dalchully, one obstruction would . . 
answer . . . the purpose of confining the waters in this direction. If 
this were a mass of alluvial matter occupying the strath in which the 
