fficers; and the goods subject to duty are
weighed and measured, and the duties estimated according to law.

Chapter XXXIII.

Power to regulate Commerce, continued. Navigation; Commerce among the
States, and with the Indian Tribes.

Sec.1. In regulating foreign commerce, congress has also passed navigation
laws. _Navigation_ is the art of conducting ships and other vessels. It
has reference also to the rules to be observed by owners and masters
engaged in the shipping trade. We have noticed the navigation acts of
Great Britain by which she built up her shipping interest; (Chap. XXVII,
Sec.7,) and we have stated that one object of the power to regulate
commerce was to countervail the effects of those acts upon our shipping.

Sec.2. To encourage and promote domestic navigation, an act was passed by
the first congress conferring special privileges upon vessels built and
owned by citizens of the United States. This was done by laying _duties
on tunnage_. _Tunnage_ means the content of a ship, or the burden that
it will carry, which is ascertained by measurement, 42 cubic feet being
allowed to a tun. This act imposed a duty of fifty cents a tun on
foreign vessels, and upon our own a duty of only six cents a tun. As
such a law discriminates, or makes a distinction or difference between
domestic and foreign vessels, these duties are also called
_discriminating_ duties.

Sec.3. By the aid of these protective duties, slightly changed from time to
time, our shipping interest acquired great strength. But the necessity
of discriminating duties no longer exists. By the stipulations of
existing treaties between the principal commercial nations, each is to
admit into her ports the vessels of the others on equal terms with her
own. Our government having become a party to this agreement,
discriminating tunnage duties have been abolished.

Sec.4. The registry, however, of vessels of the United States, and other
regulations concerning them, are for the most part continued. A vessel
is measured by a surveyor to ascertain her tunnage, and the collector
records or registers in a book her name, the port to which she belongs,
her burden or tunnage, and the name of the place in which she was built,
and gives to the owner or commander a certificate of such registry.

Sec.5. The master of a vessel departing from the United States, bound to a
foreign port, must deliver to the collector of the district, a
_manifest_, which is an in