It wil) be seen by thÃ© PresÃdenos Proclamation, that although no formal declaration of war lias been made ngainst Mexico, y et the country is declared to be "in a state of war." This, we suppose, fit mcans any thing, is meant to cover the saine ground. As to the result of the present state of a fluir, the re are vurious opiniÃ³n?. Many sensible persons are looking for another edition of the Florida war - an enormous national expense, continued for several yenrs, for tho propagation of Slavery, and the emolument of souih western Slaveholders. The newspnper campaigners are calling for an anny of 50,000 men to proceed irnmediately lo the Capital of the Mexican Republic, compel her humbly to ask for mercy, and pay all the expenses of the war: very niuch in the same way, we suppose, that the British served the Chinese. Such campaigns, however, are often more easily planned than executed. At present, we see no rcason for unticipating any very bloody or momentous iransactions ; and should the Mexican ormy on the Rio Grande be wilhdrawn, or be annihilaled, we doubt whether the invasiÃ³n of Mexico would be underlaken by our gove.nmcnt. - However, n large portion of the people are perfectly mad for extending ihe national territory : and should Mr. Polk take into bis head lo immorlalize his name by the conquest of Mexico, as his predecessor clid by the annexation of Texas, the attempt may yet be made. In the mean time, let the reader remember, that be the war longer or shorter, on a large or a small scale, t is a war for the addition of '25,000 foreign slaves to the number already existing in our own country ; and for the extensiÃ³n oÃ Slavery over a vast tract of new country, for the express purpose of upholding Slavery In the Soulli ; and that the expense, through the TariÃÃ', will be chielly paid by the Free States of the Nortli.