To the Editor of the New-York Daily Times:

  The TIMES of the 16th inst. publishes a letter from "A Southerner," dated Alabama, and, in its editorial remarks upon it, says:

"We do not mean that Congress has not the power, and in that sense the right, to repeal any law at any time. All legislative power is vested in Congress, and Congress has the power to legislate Alabama out of the Union to-morrow. But the possession of power and of legal right is not enough to establish the equity of legislation."

  If the TIMES had said that Congress has the power to legislate Slavery out of Alabama, and out the Union, it might have cited good authority for that position from the Constitution. It might have quoted the power to regulate commerce, and the limitation of the exercise of that power, by the Proviso in Art. 1, Sec. 9:

"The migration or importation of such persons as any of the States now existing shall think proper to admit, shall not be prohibited by the Congress prior to the year 1808."

  Since that date the power of Congress to prohibit either the migration or importation, or both, has been full and complete. Congress did prohibit the importation, and might, and ought, at the same time, to have prohibited the migration, under the same penalties as were enacted against importation. Migration means, and is, removal, and nothing more or less. What, then, would have been the value to any one but themselves, of such PERSONS, if Congress had prohibited their migration? What now would be the value of such PERSONS if to-morrow Congress should prohibit their migration to New-Orleans or Nebraska; from the hut to the field; from Uncle Tom's Cabin to the possession of Haley; or from the Auction-Block to Legree?

  If the Congress, which did its duty in part by prohibiting importation, had performed its whole duty by also prohibiting migration, the otherwise fair face of Alabama would never, as a State, have been disfigured by the black crime of Slavery. . . .

FRANKLIN.