s are _specific_ and _ad valorem_. A _specific_ duty is a
specified sum of money charged upon every yard, pound, or gallon of any
commodity. Thus, a duty of ten cents on a pound of tea, or of one dollar
on a yard of cloth, or of fifty cents on a gallon of wine, is a specific
duty. _Ad valorem_ is a Latin phrase, signifying _according to the
value_. An _ad valorem_ duty is a certain _per centage_ on the value or
price. Thus, thirty per cent, on a yard of cloth costing two dollars, is
sixty cents; on a yard costing three dollars, ninety cents; the sum
charged being varied by the difference in the price or value.

Sec.7. The power to lay duties is very properly qualified by the provision
that "all duties shall be uniform throughout the United States." This
was intended to prevent the giving of unjust preference to any one or
more states over others. Without this restriction upon the exercise of
this power, the representatives of a part of the states might combine,
and by laying higher duties upon goods imported into other states, than
upon those imported into their own, might turn the trade chiefly into
the latter. Or they might in laying duties on exports, impose high
duties upon the productions of other states, and low duties, or none at
all, upon the products of their own.

Sec.8. Although Congress has power to lay direct taxes, it has seldom been
exercised. The duties on foreign goods and on the vessels in which they
were imported, have been found sufficient for the payment of the public
debt, and for other government purposes. The national debt in 1791 was
about $75,000,000, and, in 1804, had risen to $86,000,000; yet chiefly
by duties was this debt reduced nearly one-half by the year 1812. By the
war which commenced that year, the debt was again increased, being in
1816, $127,000,000. In 1835, this large debt had been, in the manner
stated, entirely extinguished.

Sec.9. The next power mentioned is the "power to borrow money on the credit
of the United States." Although Congress may, under the power to lay
taxes and duties, raise money to any extent, a large amount may
sometimes be wanted before it can be raised from the regular income or
revenue of the nation, or even before it could be raised by a direct
tax, which would be burdensome to the people. Hence the utility of the
power to borrow money until it can be reimbursed from the national
revenues.

Chapter XXXII.

Power of Congress to Regulate Commerce