SATURDAY, DECEMBER 31, 1853.ESP* Rumor has for some time past intimated that a certain William Walker, of San Francisco, was preparing an expedition to make an onset upon Lower California? and to another column will be found a detailed account of his progress, and of what he deems the final triumph of his plans and purposes.In hit mind it it a fixed fad thatM William W alk-cr is ••President of Lower California;*' and his •‘Secretary of State” has formally announced the capture of the vhole country by the •• first battalion of Lower California,” consisting 44 of forty-five men,*' imported from San Francisco, and boldly asserts, after giring a list of oificers composed of strangers to the land, that •* our government has been founded upon a firm and sure basis. Thereupon •• tho President has issued hit card to the world, in the form of an * address of President Walker to the people of the United States. This will also be found in another column of our paper to-day, and we add a few comments upon that most singular document.The address purports to be issued by the President of a Republic. If it is but the silly gasconade of an ambitious but unprincipled usurper, who has only a temporary fooling in the country he assumes to govern, it is of little account, and wilt soon pass into oblivion, like some of the paper blockades of modern times; but if a Republic,—an independent Republic —has been established by the people of Lower California, and William Walker has been elected- their President, it is a matter of no small import. \ he facts however, as yet known, only impress us with the belief that Capt. Walker to an adrenturer, leading party of men from a neighboring State at peace with Mexico, who by violence, and in contravention of the laws of God and man, have imprisoned the Governor of a State in which they have no interest but as plunderers, and placed themselves in the category of outlaws and robbers. Wc are confirmed in this opinion by the reasons he has himself given for • the course he has taken,*’ and 4 why another republic is culatld ou the immediate con fines of the ‘Great Union:**'President Walker assumes that under Mexican rule the territory •* would forever remain wild, half-savage and uncultivatedand that he therefore to justified in creating a republic for •• an indolent and half-civilized people, desirous of keeping all foreigners from entering the limits of the State who, he affirms* cannot and should not lc allowed *' to play the dog *n the manger, and keep others from possessing what they have failed to occupy and appropriate.”In bis opinion, “might makes right,”—and the sovereignty of the people belongs to the strong power that covets it; the doctrine of tyrants, long since rebuked and repudiated by the civilized world. If President Walker can justify himself in creating a republic aad taking possession of Lower California upon that ground, where to the safety of the weaker States of the world ? They have none whatever.It is not for Col. Walker to dictate to the people of Lower California to whom they shall owe allegiance, end though he may have been successful in temporarily establishing himself there, and claims to be President, he will and should he without the sympathy of lie goierument cf the United States, or of any other people, to sustain him in his aggressions ; and without support from abroad, he has only placed himself m a position to be treated as an outlaw, in/asc he should Rod the people of Lower California stubborn in their dislikes to “ all foreigners.”It is for the inhabitants of a country to aay how they ihall be governed, and if it is the choice of the resi-ients of Lower California to dissolve the ties that I ind ihc State to Mexico, it to their right to declare their rhoico, without the interference or intermeddling of foreign aid *, and wc much mistake the character of the people of Lower (jj^ifornia, if they do not hold Col. SValkcr to a serious account, notwithstanding he has issumed “the divine right to rule ” over them. He i08 taken possession and plundered the gubernatorial irehivee, upon the pretext that the people arc 44 the iog in the manger,** cud they may in turn jet teach im that the •* wolf in sheep's clothing to not a wcl-lome visitor among them. •Our sympathies are always with an oppressed pco-fc who are attiring to throw off the yoke tyranny has mpo5cd upon them, and w hen the people of Lower 'alifornia are desirous of establishing an independent Bpublic, we shall aay God speed them. But until ac residents of the country are agreed to a change, sir doctrine is that they should Ik? let alone, and Col. Yalker treated as an outlaw, which, from hisoun published address, lie certainly appcanMo be.their native fountry, where we are well assured they will be welcomed by numerous friends and an approving government.Arrival the Boston.The fine, fast sailing clipper brig Boston, Capt Tapley arrived at this port yesterday, in 13 days from San Francisco. She brings papers to the 16th. No later advices from the Atlantic States or Europe had been received, but the steamer was momentarily expected with dates to the 20th Nov. from New York.The filibuster expedition, under Col. Walker had met with disaster, and one third of his force had been killed by the Lower Californians under Melendrey. It was supposed that ere this the whole baud of outlaws ha9 met their richly deserved fate. A correspondent from San Diego of Dec. 7tii says, ~ I have no sympathy with Walker’s men; from their own showing they have earned the halter, and without immediate assistance, you will soon be called upon to chronicle the attainment of their high aspirations.”The Boston has performed the voyage to San Francisco and bock in *18 d3ys. This is the quickest time yet made for the round voyage. The brig Noble once made it in 41 days, the shortest then known.