It ought not to be forgotten that the first and main object of the negotiation which led to the acquisition of Louisiana, was the free navigation of the Mississippi, a river that forms the sole passage from the western States to the ocean. This navigation, although of general benefit, has been always valued and desired, as of peculiar advantage to the Western States, whose demands to obtain it were neither equivocal nor unreasonable. But with the river Mississippi, by a sort of coercion, we acquired, by good or ill fortune, as our future measures shall determine, the whole province of Louisiana. As this acquisition was made at the common expense, it is very fairly urged that the advantages to be derived from it should also be common. This, it is said, will not happen if slavery be excluded from Missouri, as the citizens of the States where slavery is permitted will be shut out, and none but citizens of States where slavery is prohibited, can become inhabitants of Missouri. But this consequence will not arise from the proposed exclusion of slavery. The citizens of States in which slavery is allowed, like all other citizens, will be free to become inhabitants of Missouri, in like manner as they have become inhabitants of Ohio, Indiana, and Illinois, in which slavery is forbidden. The exclusion of slaves from Missouri will not, therefore, operate unequally among the citizens of the United States. The Constitution provides, "that the citizens of each State shall be entitled to enjoy all the rights and immunities of citizens of the several States"; every citizen may, therefore, remove from one to another State, and there enjoy the rights and immunities of its citizens. The proposed provision excludes slaves, not citizens, whose rights it will not, and cannot impair. Besides there is nothing new or peculiar in a provision for the exclusion of slavery; it has been established in the States north-west of the river Ohio, and has existed from the beginning in the old States where slavery is forbidden. The citizens of States where slavery is allowed, may become inhabitants of Missouri, but cannot hold slaves there, nor in any other State where slavery is prohibited. As well might the laws prohibiting slavery in the old States become the subject of complaint, as the proposed exclusion of slavery in Missouri; but there is no foundation for such complaint in either case. It is further urged, that the admission of slaves into Missouri would be limited to the slaves who are already within the United States; that their health and comfort would be promoted by their dispersion, and that their numbers would be the same whether they remain confined to the States where slavery exists, or are dispersed over the new States that may be admitted into the Union.