We have alluded only to such facts in Mr. Cushing's history as are fresh in the remembrance of our readers; and it would not have been worth our while to allude even to these, if he had not seen fit to speak of the leading men of the Republican Party as "dangerous, because they have _no fixed principle, no stable convictions, no samples of consistency to control their acts_; because their _only creed is what has been called the duty of success_; and because their success--the successful accomplishment of a sectional organization of the government on the ruins of its nationality-- would be the _de facto_ dissolution of the Union." In his Letter he says also, that "it is a fact humiliating to confess that the cant of negroism still has vogue as one of the minor instruments of demagoguy in Northern States." The coolness of such charges, coming from Mr. Cushing, is below the freezing-point of quicksilver. Shall we take lessons in fixedness of principle from the Whig-Antislavery Member from Federalist Essex?--in stable convictions from the Tyler-Commissioner to China?--in consistency from the Democratic Attorney-General?--in an amalgam of all three from the Coalition Judge? Shall we find a more pointed warning of the worthlessness of success in the words than in the example of the orator? Since Reynard the Fox donned a friar's hood, and, with the feathers still sticking in his whiskers, preached against the damnable heresy of hen-stealing, there has been nothing like this! In China, they set great store by porcelain that has been often broken and mended again with silver wire, prizing it more highly than that which is sound and fresh from the hands of the potter. There is a kind of political character of the same description, --hollow-ware, not generally porcelain, indeed,--cracked in every direction, but deftly bound together with silver strips of preferment, till it is consistent enough to serve all the need of its possessor in receiving large messes of the public pottage. How the Chinese would have admired Mr. Tyler's Commissioner, if they had known the exquisite perfection of _crackle_ displayed in his political career! To be sure, the Chinese are our antipodes.