[54]. Le Blond’s Elements of War.
[55]. Mr. Robertson, librarian of the Royal Society, favoured the author with an inspection of several curious remarks concerning the history of modern navigation; in which it appears, that the most early discoveries with regard to the magnetical variation were made about the year 1570. Mr. Robert Norman, from a variety of observations made by him nearly at that time, ascertains it to have been 11° 15´ easterly, or one point of the compass.
[56]. Euler. De la Lande.
[57]. I had often seen water-spouts at a distance, and heard many strange stories of them, but never knew any thing satisfactory of their nature or cause, until that which I saw at Antigua; which convinced me that a water-spout is a whirlwind, which becomes visible in all its dimensions by the water it carries up with it.
There appeared, not far from the mouth of the harbour of St. John’s, two or three water-spouts, one of which took its course up the harbour. Its progressive motion was slow and unequal, not in a strait line, but as it were by jerks or starts. When just by the wharf, I stood about 100 yards from it. There appeared in the water a circle of about twenty yards diameter, which to me had a dreadful though pleasing appearance. The water in this circle was violently agitated, being whisked about, and carried up into the air with great rapidity and noise, and reflected a lustre, as if the sun shined bright on that spot, which was more conspicuous, as there appeared a dark circle around it. When it made the shore, it carried up with the same violence shingles, staves, large pieces of the roofs of houses, &c. and one small wooden house it lifted entirely from the foundation on which it stood, and carried it to the distance of fourteen feet, where it settled without breaking or oversetting; and, what is remarkable, tho’ the whirlwind moved from west to east, the house moved from east to west. Two or three negroes and a white woman were killed by the fall of timber, which it carried up into the air, and dropt again. After passing through the town, I believe it was soon dissipated; for, except tearing a large limb from a tree, and part of the cover of a sugar-work near the town, I do not remember any farther damage done by it. I conclude, wishing you success in your enquiry, and am, &c.
W. M.
[58]. The swiftness of the wind in a great storm is not more than 50 or 60 miles in an hour; and a common brisk gale is about 15 miles an hour. Robertson’s Navigation.
[59]. This manœuvre, according to the best of my information, is entirely unknown to our mariners; it is performed by lining, or doubling, the flukes of an anchor, with two pieces of plank, to strengthen them, and prevent their turning in a bad anchoring-ground.
[60]. According to the arrangement of the French navy, this class comprehends all vessels of war from 50 to 20 guns.
[61]. M. Saverien defines this to be a wind perpendicular to the ship’s course, and, consequently, a wind upon the beam; but I have ventured to correct this explanation, by the authority of M. Aubin, who is certainly right in his description.