386 Proceedings of the Royal Physical Society. 
give a little more information, and thus, by adding another 
stone to the cairn, advance glacial science. 
Our first landing was at Lerwick, where little time was spent 
either then or when returning. In a short walk that I took 
in the immediate vicinity of the towm, at the Bay of Sclate, 
I found the sandstone on the top of the cliff deeply rutted, 
striated, and polished; and a little inland, on the side of the 
famed loch of Clickamin, similar markings. They may be 
seen also on the opposite side of the bay. The ruts, &c., are 
all in a north and south direction, with slight deviations to 
the east and west. The drift evidently came from the 
north, and may be traced up the valley, as shown by the 
wide-spread ruin and large blocks scattered all over it, rest- 
ing on striated and polished rocks. The hills on each side 
of this valley, and those at the head beyond the docks, bear 
unmistakeable evidence also of polishing and grinding. 
After leaving Lerwick the Out Skerries of Whalsey 
became our home. The three small islands forming this 
group lie far out to sea. They are called Gruna, Bruray, 
and Housay. There is a pretty good harbour here, having 
two entrances for vessels and boats, and a third into which 
boats can run when the tide answers. These entrances are 
triradiate, with the harbour in the centre, sheltered by the 
three islands from every wind. The islands have been the 
scene of great grinding, all being more or less rounded into 
the Roches moutounnes form, whether composed of granite, 
gneiss, quartz, or limestone, all these rocks being inter- 
. mingled throughout the group. Although corroded by 
atmospheric action, — the limestone, as might be expected, 
most deeply cut, — the rounding can be everywhere seen.* 
Striae, &c., in the exposed parts, are thus generally oblite- 
rated. I was, however, fortunate enough to meet with re- 
* To show how abundant lime is in this rock, I obtained living specimens 
of Saxicava rugosa burrowed into it in the Skerries harbour ; they were very 
abundant, and had riddled the limestone beds in all directions. This is rather 
against the opinion of those who consider that this mollusc could not live so 
far north, and who stoutly opposed me when I said that they occurred in situ 
at Wick. It was, therefore, somewhat gratifying to me to meet with them so 
much further north. 
