mmercial regulation must be exclusively
committed to a single hand. What is it that is to be regulated? Not the
commerce of the several States, respectively, but the commerce of the
United States. Henceforth, the commerce of the States was to be a unit;
and the system by which it was to exist and be governed, must
necessarily be complete, entire and uniform." At the same time Webster
conceded "that the words used in the Constitution, 'to regulate
commerce,' are so very general and extensive, that they might be
construed to cover a vast field of legislation, part of which has always
been occupied by State laws; and therefore, the words must have a
reasonable construction, and the power should be considered as
exclusively vested in Congress, so far, and so far only, as the nature
of the power requires."[527]

Webster also dealt with the problem which arises when Congress has
exercised its power. The results of its act, he contended, must be
treated as a unit, so that when Congress had left subject matter within
its jurisdiction unregulated, it must be deemed to have done so of
design, and its omissions, or silences, accordingly be left undisturbed
by State action. Although Marshall, because he thought the New York act
creating the Livingston-Fulton monopoly to be in direct conflict with
the Enrolling and Licensing Act of 1793, was not compelled to pass on
either of Webster's theories, he indicated his sympathy with them.[528]

COOLEY _v._ BOARD OF PORT WARDENS

Aside from Marshall's opinion in 1827 in Brown _v._ Maryland,[529] in
which the famous "original package" formula made its debut, the most
important utterance of the Court touching interpretation of the commerce
clause as a restriction on State legislative power is that for which
Cooley _v._ Board of Wardens of Port of Philadelphia,[530] decided in
1851, is usually cited. The question at issue was the validity of a
Pennsylvania pilotage act so far as it applied to vessels engaged in
foreign commerce and the coastwise trade. The Court, speaking through
Justice Curtis, sustained the act on the basis of a distinction between
those subjects of commerce which "imperatively demand a single uniform
rule" operating throughout the country and those which "as imperatively"
demand "that diversity which alone can meet the local necessities of
navigation," that is to say, of commerce. As to the former the Court
held Congress's power to be "exclusive"--as to the latter it he