than the daily supply of the before-mentioned eighths; which,
as the Portuguese ounce is somewhat lighter than our troy ounce, may
amount to about nine shillings sterling.

[Footnote 5: On the data of the text, and allowing sixty-five days
in the year for Sundays and high festivals, the yearly profit of one
slave to his master would be L. 135 sterling.--E.]

The quantity of gold thus collected in the Brazils and returned
annually to Lisbon, may be estimated, in some degree, from the amount
of the royal fifth. This has been of late computed, one year with
another, at one hundred and fifty _aroues_, of thirty-two Portuguese
pounds each, which, valued at L. 4 sterling the troy ounce, make very
nearly three hundred thousand pounds sterling; and consequently the
capital, of which this is the fifth, is about a million and a half
sterling. It is obvious that the annual return of gold to Lisbon
cannot be less than this, though it may be difficult to guess how much
more it may be. Perhaps we may not be much mistaken in conjecturing
that the gold exchanged with the Spaniards at Buenos Ayres for silver,
and what is privately brought to Europe without paying the duty, may
amount to near half a million more, which will make the entire yearly
produce of Brazilian gold nearly two millions sterling; a prodigious
sum to be found in a country which only a few years since was not
known to furnish a single grain.

Besides gold, this country also affords diamonds, as already
mentioned. The discovery of these valuable stones is much more recent
even than that of gold, as it is scarcely twenty years since the first
were brought to Europe.[6] They are found in the same manner as gold,
in the gullies of torrents and beds of rivers, but only in particular
places, and by no means so universally spread throughout the country.
They were often found while washing for gold, before they were known
to be diamonds, and were consequently thrown away along with the
sand and gravel; and it is well remembered that numbers of very large
stones, which would have made the fortunes of the possessors, have
passed unregarded through the hands of those who now impatiently
support the mortifying reflection. However, about twenty years since,
[that is, in 1720,] a person acquainted with the appearance of rough
diamonds, conceived that these pebbles, as they were then called, were
of the same kind; yet it is said there was a considerable interval
between the firs