part of a man's wants which the produce of
his own labour can supply. He supplies the
far greater part of them by exchanging that
surplus part of the produce of his own labour,
which is over and above his own consumption,
for such parts of the produce of other men's
labour as he has occasion for. Every man
thus lives by exchanging, or becomes, in some
measure, a merchant, and the society itself
grows to be what is properly a commercial society.
But when the division of labour first began
to take place, this power of exchanging must
frequently have been very much clogged and
embarrassed in in operations. One man, we
shall suppose, has more of a certain commodity
than he himself has occasion for, while
another has less. The former, consequently,
would be glad to dispose of, and the latter to
purchase, a part of this superfluity. But if
this latter should chance to have nothing that
the former stands in need of, no exchange can
be made between them. The butcher has
more meat in his shop than he himself can
consume, and the brewer and the baker would
each of them be willing to purchase a part of
it. But they have nothing to offer in exchange,
except the different productions of
their respective trades, and the butcher is already
provided with all the bread and beer
which he has immediate occasion for. No exchange
can, in this case, be made between
them. He cannot be their merchant, nor they
his customers; and they are all of them thus
mutually less serviceable to one another. In
order to avoid the inconveniency of such situations,
every prudent man in every period
of society, after the first establishment of the
division of labour, must naturally have endeavoured
to manage his affairs in such a
manner, as to have at all times by him, besides
the peculiar produce of his own industry,
a certain quantity of some one commodity
or other, such as he imagined few people
would be likely to refuse in exchange for the
produce of their industry. Many different
commodities, it is probable, were successively
both thought of and employed for this purpose.
In the rude ages of society, cattle are
said to have been the common instrument of
commerce; and, though they must have been
a most inconvenient one, yet, in old times, we
find things were frequently valued according
to the number of cattle which had been given
in exchange for them. The armour of Diomede,
says Homer, cost only nine oxen; but
that of Glaucus cost a hundred oxen. Salt
is said to be the common instrument of commerce
and exchanges in Abyssinia; a species
of shells in some parts of the coast of India;
dried cod at Newfoundland; tobacco in Virginia;
sugar in some of our West India colonies;
hides or dressed leather in some other
countries; and there is at this day a village
in Scotland, where it is not uncommon, I am
told, for a workman to carry nails instead of
money to the baker's shop or the ale-house.
In all countries, however, men seem at last
to have been determined by irresistible reasons
to give the preference, for this employment,
to metals above every other commodity.
Metals can not only be kept with as little loss
as any other commodity, scarce any thing being
less perishable than they are, but they can
likewise, without any loss, be divided into any
number of parts, as by fusion those parts can
easily be re-united again; a quality which no
other equally durable commodities possess, and
which, more than any other quality, renders
them fit to be the instruments of commerce
and circulation. The man who wanted to buy
salt, for example, and had nothing but cattle
to give in exchange for it, must have been obliged
to buy salt to the value of a whole ox,
or a whole sheep, at a time. He could seldom
buy less than this, because what he was
to give for it could seldom be divided without
loss; and if he had a mind to buy more, he
must, for the same reasons, have been obliged
to buy double or triple the quantity, the value,
to wit, of two or three oxen, or of two or
three sheep. If, on the contrary, instead of
sheep or oxen, he had metals to give in exchange
for it, he could easily proportion the
quantity of the metal to the precise quantity
of the commodity which he had immediate occasion
for.
Different metals have been made use of by
different nations for this purpose. Iron was
the common instrument of commerce among
the ancient Spartans, copper among the ancient
Romans, and gold and silver among all
rich and commercial nations.
Those metals seem originally to have been
made use of for this purpose in rude bars,
without any stamp or coinage. Thus we are
told by Pliny[6], upon the authority of Timæus,
an ancient historian, that, till the time of
Servius Tullius, the Romans had no coined
money, but made use of unstamped bars of
copper, to purchase whatever they had occasion
for. These rude bars, therefore, performed
at this time the function of money.
The use of metals in this rude state was attended
with two very considerable inconveniences;
first, with the trouble of weighing, and
secondly, with that of assaying them. In the
precious metals, where a small difference in
the quantity makes a great difference in the
value, even the business of weighing, with
proper exactness, requires at least very accurate
weights and scales. The weighing of
gold, in particular, is an operation of some
nicety. In the coarser metals, indeed, where
a small error would be of little consequence,
less accuracy would, no doubt, be necessary.
Yet we should find it excessively troublesome
if every time a poor man had occasion either