ing the Ohio to be so regulated as not to
interfere with it.[344] This act the Court sustained as within
Congress's power under the commerce clause, saying: "So far, * * *, as
this bridge created an obstruction to the free navigation of the river,
in view of the previous acts of Congress, they [the said acts] are to be
regarded as modified by this subsequent legislation; and, although it
still may be an obstruction in fact, [it] is not so in the contemplation
of law. * * * That body [Congress] having in the exercise of this power,
regulated the navigation consistent with its preservation and
continuation, the authority to maintain it would seem to be complete.
That authority combines the concurrent powers of both governments, State
and federal, which, if not sufficient, certainly none can be found in
our system of government."[345] In short, it is Congress and not the
Court which is authorized by the Constitution to regulate commerce.

The law and doctrine of the earlier cases with respect to the fostering
and protection of navigation are well summed up in the following
frequently cited passage from the Court's opinion in Gilman _v._
Philadelphia,[346] decided in 1866. "Commerce includes navigation. The
power to regulate commerce comprehends the control for that purpose, and
to the extent necessary, of all the navigable waters of the United
States which are accessible from a State other than those in which they
lie. For this purpose they are the public property of the nation, and
subject to all requisite legislation by Congress. This necessarily
includes the power to keep them open and free from any obstruction to
their navigation, interposed by the States or otherwise; to remove such
obstructions when they exist; and to provide, by such sanctions as they
may deem proper, against the occurrence of the evil and for the
punishment of offenders. For these purposes, Congress possesses all the
powers which existed in the States before the adoption of the national
Constitution, and which have always existed in the Parliament in
England."[347]

Thus Congress was within its powers in vesting the Secretary of War with
power to determine whether a structure of any nature in or over a
navigable stream is an obstruction to navigation and to order its
abatement if he so finds.[348] Nor is the United States required to
compensate the owners of such structures for their loss, since they were
always subject to the servitude represente