It is the maintenance of slavery by law in a state, not parallels of latitude, that makes its a southern state; and the absence of this, that makes it a northern state.
The proposition of an established classification of states as slave states and free states, as insisted on by some, and into northern and southern, as maintained by others, seems to me purely imaginary, and of course the supposed equilibrium of those classes a mere conceit.
But the Constitution was made not only for southern and northern states, but for states neither northern nor southern, namely, the western states, their coming in being foreseen and provided for.