From the New York Advertiser.

Conventions were in session during the last week, both in South Carolina and Georgia, for the purpose of obtaining relief from the alleged oppressions of the tariff laws. The South Carolina politicians proposed to accomplish their object by a system of nullification; the Georgians, if we understand their sentiments by secession from the union. The latter condemn nullification in very decided terms and at the same time claim the power as well as the right of seceding from the Union, whenever in their opinion the national government transcends its constitutional limits. Now it seems to us, that the distinction which is so zealously contended for by these two classes of politicians is hardly worth the labor of an argument. However widely they may nominally, or professedly differ, they must both meet at the point if they carry their measure into effect, and that point is the severance of the Union. That being the necessary result of their measures, it is a matter of little moment whether it is accomplished under the name of nullification, or by a voluntary secession from the Union. That the measures of both lead to this result, cannot be questioned. In the case of Georgia it is their avowed object. When, or to what manner, it is to be brought about, it is thus far pointed out.- They may withdraw their senators and Representatives from Congress, and give notice in for to the national government, that henceforward they will have no connection with the Union; or, when the time occurs, they may resist the execution of the laws, and the decrees of the Judiciary, and thus stop by force the powers of the government over them. The South Carolina plan seems to be to resist the government by preventing the collection of customs, and resisting the enforcement of the revenue laws. Georgia purposes to make it a highly criminal offence of a lawyer, employed as council by a Cherokee, to question the constitutionality of their legislative acts extending jurisdiction over the Indian country, or to assist in carrying into effect the judgement of the Supreme Court in the Missionary case. The last measure, when carried in execution, will be levying war against the United States.

We should think it hardly worth while for the politicians of Georgia to condemn those of South Carolina, in the prosecution of their system of measures in opposition to the laws of government of the Union. The plans of both states are incompatible with their obligations, as members of the confederation, to support the Constitution and laws of the United States, that Georgia being, in our judgment, the most flagrant of the two. In both instances, the claim the right of determining for themselves what laws of Congress are, and what are not constitutional, thereby denying the legitimate authority of the Judicial branch of the government. Each may pursue a different course in reaching the object in view; but when accomplished, the effects upon the Union, and the national government, will be precisely the same.

Since the above was in type, we see by a Charleston paper, that a part of the Georgia convention have protested against the further proceedings of that body, on the ground that a large portion of the State is not represented. We publish the protest this morning.