I sent Mr. Macurich, a shipmaster in the lighthouse service, to the Calf of Man, with directions to reside there, and make monthly returns of the state of the weather, agreeably to a printed form. During his stay of seven months, it appears upon the whole that the fog rested only twice upon the highest land of the Calf Island, while257 it cleared partially below. On one of these occasions I was on board of the lighthouse yacht, then at anchor off the island, when the fog was for a time general; and as the weather became clear, I observed that it first disappeared upon the lower parts of the island, and that in half an hour the whole of the Calf was seen. In the monthly returns made by Mr. Macurich, the Calf island is represented as often perfectly free of fog, while the higher parts of the opposite mainland of the Isle of Man were hid in mist. To account for this, it may be noticed that the mass of matter in the Calf Island is much less, and the land is also much lower than in the main island. Part of this effect may also be ascribed to the rapidity of the tides, which create a current of wind, particularly in the narrow channel between the main and Calf islands, which have a direct tendency to clear away the fog, as I have observed at the Skerries in the Pentland Firth, and in similar situations on different parts of the coast, where rapid currents prevail.鈥�

The union of Hoylake and the Rock Channel formed, as at present, the principal passage to sea, called the Horse Channel, then138 a fair opening with three to seven fathoms, but considerably to the eastward of the present channel of that name; for Collins鈥檚 sailing mark through it was Mockbeggar Hall upon the Banquetting-House in Bidston, would mark the present Spencer鈥檚 Gut as having been the channel. The north spit did not then exist, or rather was part of the Hoyle bank; and the Beggar鈥檚 Patch seems to have been the extremity of Dove Point. The Formby Channel was said to have three fathoms on the bar, but was not buoyed or beaconed, therefore not used.

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The unlocking of screws, where washers had been introduced as a security was rather unexpected, and the writer took an opportunity of conversing with his much respected friend Professor Playfair regarding this circumstance. The Professor observed, that he had experienced some inconvenience of this kind from the unlocking of almost all the screws of a telescope which had been sent to him from London by the mail coach. Indeed, from the spiral form of the screw, which is, in fact, an inclined plane, Mr. Playfair readily accounted for such an occurrence, and, when reflected upon, it seems to be an effect rather to be looked for, and is a reason why riveting the point of a bolt in preference to screwing it should generally be resorted to, where much motion is to be apprehended.鈥�