trade one time here, another time there, and with very good success too.
But I say, be that as it will, a tradesman ought so far to acquaint
himself with business, that he should not be at a loss to turn his hand
to this or that trade, as occasion presents, whether in or out of the
way of his ordinary dealing, as we have often seen done in London and
other places, and sometimes with good success.

This acquainting himself with business does not intimate that he should
learn every trade, or enter into the mystery of every employment. That
cannot well be; but that he should have a true notion of business in
general, and a knowledge how and in what manner it is carried on; that
he should know where every manufacture is made, and how bought at first
hand; that he should know which are the proper markets, and what the
particular kinds of goods to exchange at those markets; that he should
know the manner how every manufacture is managed, and the method of
their sale.

It cannot be expected that he should have judgment in the choice of all
kinds of goods, though in a great many he may have judgment too: but
there is a general understanding in trade, which every tradesman both
may and ought to arrive to; and this perfectly qualifies him to engage
in any new undertaking, and to embark with other persons better
qualified than himself in any new trade, which he was not in before; in
which, though he may not have a particular knowledge and judgment in the
goods they are to deal in or to make, yet, having the benefit of the
knowledge his new partner is master of, and being himself apt to take
in all additional lights, he soon becomes experienced, and the knowledge
of all the other parts of business qualifies him to be a sufficient
partner. For example--A.B. was bred a dry-salter, and he goes in partner
with with C.D., a scarlet-dyer, called a bow-dyer, at Wandsworth.