variation, by the mean of several
azimuths taken with three different compasses, was 9 deg. 32 1/2' W. At
eleven o'clock, one extreme of Mayo bore E. by N., and the other S.E. by
S. In this position, two roundish hills appeared near its N.E. part;
farther on, a large and higher hill; and, at about two-thirds of its
length, a single one that is peaked. At the distance we now saw this
island, which was three or four miles, there was not the least
appearance of vegetation, nor any relief to the eye from that lifeless
brown which prevails in countries under the Torrid Zone that are
unwooded.

Here I cannot help remarking that Mr Nichelson, in his Preface to
"Sundry Remarks and Observations made in a Voyage to the East
Indies,"[80] tells us, that "with eight degrees west variation, or any
thing above that, you may venture to sail by the Cape de Verde Islands
night or day, being well assured, with that variation, that you are to
the eastward of them." Such an assertion might prove of dangerous
consequence, were there any that would implicitly trust to it. We also
tried the current, and found one setting S.W. by W., something more than
half a mile an hour. We had reason to expect this, from the differences
between the longitude given by the watch and dead reckoning, which,
since our leaving Teneriffe, amounted to one degree.

[Footnote 80: On board his majesty's ship Elizabeth, from 1758 to 1764;
by William Nichelson, master of the said ship.--London, 1773.]

While we were amongst these islands, we had light breezes of wind,
varying from the S.E. to E., and some calms. This shews that the Cape de
Verde islands are either extensive enough to break the current of the
trade wind, or that they are situated just beyond its verge, in that
space where the variable winds, found on getting near the Line, begin.
The first supposition, however, is the most probable, as Dampier found
the wind westerly here in the month of February; at which time the trade
wind is supposed to extend farthest toward the equinoctial.[81] The
weather was hot and sultry, with some rain; and, for the most part, a
dull whiteness prevailed in the sky, that seems a medium between fog and
clouds. In general, the tropical regions seldom enjoy that clear
atmosphere observable where variable winds blow; nor does the sun shine
with such brightness. This circumtance, however, seems an advantage; for
otherwise, perhaps, the rays of the sun, being uninterrupted, would