Now there are in the United States, the results of State or private enterprise, upward of 17,000 miles of railroads and 5,000 miles of canals; in all, 22,000 miles, the total cost of which may be estimated at little short of $600,000,000; and if the same works had been constructed by the Federal Government, supposing the thing to have been practicable, the cost would have probably been not less than $900,000,000. The number of persons employed in superintending, managing, and keeping up these canals and railroads may be stated at 126,000 or thereabouts, to which are to be added 70,000 or 80,000 employed on the railroads in construction, making a total of at least 200,000 persons, representing in families nearly 1,000,000 souls, employed on or maintained by this one class of public works in the United States. In view of all this, it is not easy to estimate the disastrous consequences which must have resulted from such extended local improvements being undertaken by the General Government. State legislation upon this subject would have been suspended and private enterprise paralyzed, while applications for appropriations would have perverted the legislation of Congress, exhausted the National Treasury, and left the people burdened with a heavy public debt, beyond the capacity of generations to discharge. Is it conceivable that the framers of the Constitution intended that authority drawing after it such immense consequences should be inferred by implication as the incident of enumerated powers? I can not think this, and the impossibility of supposing it would be still more glaring if similar calculations were carried out in regard to the numerous objects of material, moral, and political usefulness of which the idea of internal improvement admits. It may be safely inferred that if the framers of the Constitution had intended to confer the power to make appropriations for the objects indicated, it would have been enumerated among the grants expressly made to Congress.. When, therefore, any one of the powers actually enumerated is adduced or referred to as the ground of an assumption to warrant the incidental or implied power of "internal improvement," that hypothesis must be rejected, or at least can be no further admitted than as the particular act of internal improvement may happen to be necessary to the exercise of the granted power. Thus, when the object of a given road, the clearing of a particular channel, or the construction of a particular harbor of refuge is manifestly required by the exigencies of the naval or military service of the country, then it seems to me undeniable that it may be constitutionally comprehended in the powers to declare war, to provide and maintain a navy, and to raise and support armies. At the same time, it would be a misuse of these powers and a violation of the Constitution to undertake to build upon them a great system of internal improvements.