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Towards Madeira.]

July 18 we sailed from Spithead; and in the afternoon of the 20th, having a light breeze from the eastward, with fine weather, our departure was taken from the Start, bearing N. 18° W. five or six leagues. On the following day we fell in with vice-admiral Sir Andrew Mitchell, with a detachment of four three-decked ships from the grand fleet cruizing before Brest. It was gratifying to learn from the admiral, that although he had not dropped an anchor for seventeen weeks, there was not a scorbutic man on board; nor any in the sick list, except from slight hurts.

The variation of the compass off St. Alban's Head, had been observed by Mr. Thistle, the master, to be 28° 43′ west, from amplitude; off the Start it was 29° 34′ from a western azimuth, and 29° 30′ from amplitude; but on the following afternoon, where the variation should have been nearly the same, azimuths gave 24° 12′ and an amplitude 23° 43' west; the mean 5° 35′ less than off the Start. The same compass was always used, and the ship's head was at west (magnetic), or within one point of it, in all the cases; but in the first observations the compass was placed on the binnacle,