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of Edinburgh , Session 1878 - 79 . 
their N.W. than at their S.E. ends. This change in the striae can be 
accounted for by supposing that the striating agent as it moved over 
the rock, acted with a lessening pressure, by having rebounded 
from the rock after the first impact. 
5. On Mingary Hill, reaching a height of about 600 feet above 
the sea, three miles N.E. of Askernish, many boulders occur, 
especially, as usual, on the N.W. flanks. Most of them occupy 
separate spots — but in some places they are in clusters — heaped on one 
another. In this last class of cases, there is generally a knoll of 
some kind standing up above the general surface, on or round 
which the boulders lie. 
One of the most interesting spots on this hill is a spur from it 
projecting N.W., to which Mr Drever (who resides at Askernish), 
conducted the Convener. His object was to point out there a 
boulder of considerable size which had shortly before been seen 
by Mr Jolly of Inverness. The hill in question is shown in 
fig. 19. The hill here reaches to a height of 270 feet above 
the sea, and it slopes down at an angle of about 15° to the 
N.W. But about 30 or 35 feet from the top, there is a horizontal 
plateau, on which a number of boulders lie together. Has 
this been an old sea-margin, from which the smaller stones have 
been washed away, leaving on it, as on a beach, the heavier 
boulders ? The largest boulder in the figure, lower than all the rest, 
is 11 x 9 x 8 feet. It lies on bare rock sloping down towards the 
N.W., from which quarter it, as well as all the others, had appa- 
rently come. The transporting agent seems to have struck upon the 
hill, and discharged its cargo there. 
Very near the top of the hill, there is a rocky surface, rounded 
and striated, the striae running N.W. by N. A vein of quartz 
about 3 inches wide crosses this rock, and for about 12 inches it 
presents a beautifully smoothed surface. 
6, At a place called Jocdar, situated on the main road one and 
a half mile south of the Ferry between Uist and Benbecula, 
smoothed rocks have been exposed to view by the removal of 
gravel, &c. These rocks are at a height of about 25 feet above the 
sea. The rocks are literally covered by parallel striae, ruts, and 
grooves, the direction of all which is N.W. by W. 
On these rocks there are twelve or fourteen deep ruts and 
