One beautiful morning, during our stay of six days at the Rock, we had a visit from a shoal of small fish, whose novel appearance made me take them for a fleet of some species of Nautilus. Those animals came in such numbers, that the pale blue silky membranes or sails, which wafted them before a gentle breeze over the glassy surface of the ocean, literally covered the water as far as we could see. One of those animals I sent in a small phial to my friend, Professor Fleming, then of King’s College, Aberdeen, who assigns to it the Linnean name of _Medusa velilla_, and says it is noticed by Dr Walker and Mr Pennant, as a native of Scotland. ~Driven by a gale to Mull.~ ~Return to Hynish, and are driven to Coll.~ ~Return to the Rock.~ The threatening of the previous night was fully verified by the succeeding Sunday morning, as a strong southerly wind with heavy showers, forced us to part from our moorings at the Rock at break of day, and make sail for Hynish Bay, where we anchored at seven. On Monday I landed at Hynish; but as the wind, which had increased to a strong gale, was still rising and inclining more to E., Mr Macurich summoned me to the boat, when, with much difficulty, and at the expense of shipping several seas, we reached the vessel which was pitching the bowsprit under. This soon forced us to run for the Sound of Mull, where we were detained until Saturday the 25th, on the morning of which day we again made Hynish Bay; but the wind, which had been less violent when we started from Tobermory the night before, again commencing to blow strong from the same unpropitious quarter, we had only time to land at Hynish, and take on board a salted sheep (which proved a rather unpalatable addition to our provisions), when we were forced to seek shelter in our old quarters at Loch Erin in Coll. As we entered Loch Erin, we saw the _Regent_ (the General Lighthouse Tender) leave the Sound of Mull, and again put back to Tobermory. Next day (the 26th August) we left Loch Erin, and boarded the Regent; but the weather proving boisterous, we were again forced into our old anchorage, while the _Regent_ proceeded with the Engineer, who was then on his annual voyage, to Barrahead Lighthouse, without attempting to go near the Skerryvore. From this date the weather did not prove favourable for a landing until the 30th, when the wind being N.W., we sailed from Loch Erin at daybreak, and reached the Skerryvore at ten. We now discharged all the remaining materials which had been shipped for the Rock with a view to complete the pyramid of the barrack, which it was intended should stand the test of a winter, deferring the fixing of the habitable part till next spring. ~Driven to Tyree.~ ~Return to the Rock.~ ~Horizontal braces fixed.~ ~Driven to Mull.~ ~Heavy gale.~ ~Timber cast on Tyree.~ ~Return to Rock, and farther progress of barrack.~