CH. XXIII.]
POWERS OF CONGRESS—CESSIONS.
107
erate through the Union, and may use the last in aid of the first; or, because the power of exercising exclusive legislation draws after it, as an incident, the power of making that legislation effectual; and the incidental power may be exercised throughout the Union, because the principal power is given to that body, as the legislature of the Union.
So, in the same act, a person, who, having knowledge of the commission of murder, or other felony, on the high seas, or within any fort, arsenal, dock-yard, magazine, or other place, or district of country within the sole and exclusive jurisdiction of the United States, shall conceal the same, &c. he shall be adjudged guilty of misprision of felony, and shall be adjudged to be imprisoned, &c. It is clear, that congress cannot punish felonies generally; and, of consequence, cannot punish misprision of felony. It is equally clear, that a state legislature, the state of Maryland for example, cannot punish those, who, in another state, conceal a felony committed in Maryland. How, then, is it, that congress, legislating exclusively for a fort, punishes those, who, out of that fort, conceal a felony committed within it?
The solution, and the only solution of the difficulty, is, that the power vested in congress, as the legislature of the United States, to legislate exclusively within any place ceded by a state, carries with it, as an incident, the right to make that power effectual. If a felon escape out of the state, in which the act has been committed, the government cannot pursue him into another state, and apprehend him there; but must demand him from the executive power of that other state. If congress were to be considered merely, as the local legislature for the fort, or other place, in which the of-
