Our intelligenco trom St. Domingo this morning is uf unusual interest. - Our domestic dissc:.sions are producing théir natural fmits. The tenor of the American name is jrono, and the Pmvors ot the Old World are flocking to the feast from whieh the scream of our eagle has bitnerto scarod thern. - Wc aro jast beginning to suffer llie pcnalties oí' boing a iroak and de6piaed Power. Spuin lias virtually seized upon the Island of St. Domingo. On the 22d inst., tho Spániéh frigate Blanco leit the port of Havana, witli 1,000 troops on board, on nis niission, and in a day or two anther was posiüvely to sail wilh the saine number, and on tho same errand, 'l'ho mero rumor has now become i certainty tliat President Pantana has sold the Iudepondence of San Domingo lo Spain. Wo are aware that his ellorts to this end, horetof .re and ior some yeara past, have been fruitle.ss; but now we have every reason to buiicvethat Spain has not only consentttd to an entire annexation of that Bepüblic, but that, at this moment, the ; Spanish ilag is flviog over it. In tho : ineanwhile the negroos, tlie true owners of the Boil, ara p a state of cormal ' surroction. Thíey oull upon each othcr to die in the sacred cause of personal und politioal liberty. 'l'hoy sav, and with reason, th-.it the Spanish Government cannot exist upon that island without the insutution of slavery, and thut, if they themselves are not to be onslaved, the e.xtermination of their race, as freemen, will be an inevitable resjlt. The proptfgaWdisra of Slavery is engratted upon the colonizibg policy of' Spain, and with all tht forco of a new birth - a regeneratiun as a Pbwr upon earth - she is detennined to enforce it. Aro ivo already so dead to the grand principie ot human liberty, so lost toa sense of our own nationality, so absorbed in intornouinc feu ds, as quietly to permit this fooi usurpation over the rights of freemen - and ihat, too, withiu ucable's longth of our ouu shoro ? Spain, even baughty and proud as she feels of her new-born power, wo'ild not dare to take such a stop, did she not realizo that hor true strengt!) lies in the weakuess and distractions of our own councils. Our dissensions have been weloomed by her as otfering precisely the opportunity she desires for resumí ng her position :is a Power on the Western Continent. One of the lèadïüg Madrid jouruals, a few daj's since, tlius noticed our seuossion moveinent : '' The troubles now tbrëateniog tho existenco of tho American Union aio ■not subjecls of grii f to the people of Spain. Her polilical integnty, her interests of' race, of religión and her policy, roquire that a slop bo put to the progress of this swelling population. lf it woro proper to bo ple ised with otlier people's misfortunes, Spain could, perhaps, havo roason to téjóice at what is happening on tho othor side of the oeoan.1' But San Domingo is not the only direction lowards which Spanish usurpation is tending Gen. Miramoa, late President of Mexico, has arrived in this city. en route to Spain, whither Señor Pacheco, late Spanish Minister to Mexico, has already gone ; and the object of both of tho.o gentlemen is to urgo upon the willing ears of the Spanish Qlieeo the facdity of restoring thi long-lost jewel to lier anctstral crown. We do not roalize the Sllddeu stridos cl' Spain towards her pristine greatness; we do not t-eo her young fleets of splendid steamers, and her well-clad troops, and but few o" us know Ihat sho has at pressnt in her Treasury tho snug surn of twentyseven miliions of dol la re; yet we all rèrnember her history, and its leseóos ought to teach us that, with the return of lier power and slrength, will be sure to como the desire of reconquest.