e power of Congress, at once, upon all these minor
objects of legislation? If all these be regulations of commerce, within
the meaning of the Constitution, then certainly Congress, having a
concurrent power to regulate commerce, may establish ferries,
turnpike-roads, and bridges, and provide for all this detail of interior
legislation. To sustain the interference of the State in a high concern
of maritime commerce, the argument adopts a principle which acknowledges
the right of Congress over a vast scope of internal legislation, which
no one has heretofore supposed to be within its powers. But this is not
all; for it is admitted that, when Congress and the States have power to
legislate over the same subject, the power of Congress, when exercised,
controls or extinguishes the State power; and therefore the consequence
would seem to follow, from the argument, that all State legislation over
such subjects as have been mentioned is, at all times, liable to the
superior power of Congress; a consequence which no one would admit for a
moment. The truth is, in my judgment, that all these things are, in
their general character, rather regulations of police than of commerce,
in the constitutional understanding of that term. A road, indeed, may be
a matter of great commercial concern. In many cases it is so; and when
it is so, there is no doubt of the power of Congress to make it. But,
generally speaking, roads, and bridges, and ferries, though of course
they affect commerce and intercourse, do not possess such importance and
elevation as to be deemed commercial regulations. A reasonable
construction must be given to the Constitution; and such construction is
as necessary to the just power of the States, as to the authority of
Congress. Quarantine laws, for example, may be considered as affecting
commerce; yet they are, in their nature, health laws. In England, we
speak of the power of regulating commerce as in Parliament, or the king,
as arbiter of commerce; yet the city of London enacts health laws. Would
any one infer from that circumstance, that the city of London had
concurrent power with Parliament or the crown to regulate commerce? or
that it might grant a monopoly of the navigation of the Thames? While a
health law is reasonable, it is a health law; but if, under color of it,
enactments should be made for other purposes, such enactments might be
void.

In the discussion in the New York courts, no small reliance was placed