AS[From the Green.burg Press. I triOH KNOW-NOTHTNGISM. 1 thThe following extract of a letter from the Rev. Wm. Flynn, an Irish Methodist Preacher, of Kentucky, to his son in this county, we pub liah by request:FaA.vx.rort, Ky., Jan. 6, 1855.Deab Son : Yon wish to knew my opinionabout the Know-Nothings; and if there are-any in our State. I hare it from good authority that there are in Kentucky not less than 60,-000: and by the time the next election comes on there will be at least 100,000, composed as I believe, of the best and most patriotic citizens. I look upon it as purely au American movement—as the breaking forth of the great recuperative power of the patriotic American people in their own defence. If I am properly informed as to their intention, it is to do what should have been done years ago, but better late than never. And if they do not do it nowwhen it can be done quietly by the ballot-box. the time will come when, if done at all, it will be done through seas of blood.1 never did believe that a Roman Catholic could be an American citizen, and no doubt you have often heard me say so. I saw them naturalized in Philadelphia by the hundred and beard their vouchers swear that they were sober and industrious and well inclined towards theprinciples of the American Constitution of thlt;on of the United States, when at the same time the fellow who vouched, and the gang who were swearing to be faithful to the Constitution, were all of them drunk. I could ever be made to believe that American liberty or the Constitution would weigh a feather when the interest of their church would comein competition.I never was surprised at their connection with the Democratic party. Bishop Hughes stood as an idle spectator in the struggle going on between the Whig and Democratic parties;care a fie-about one or the other, on-or as mignt further his darling ooje easy for nim, who was not interestedthe success of either, to see wnicn 01 tne two would best suit his purpose; and the sequel fully justifies his judgment.I have been for a long time fully satisfied that the Roman Catholic church is a thousand times more guilty of treason against the government of the United Stetee then Arnoldor Burr ever could have been, and infinitely more dangerous; and the elements of danger are daily increasing. Circumstances have changed greatly since I came to the United States, in 1816. Then passages were high, and none but the middle and upper classes of society could find means tothat O’Connel and his party had strongascendancy in Ireland:hopes ofana they £ben saTd, “Let the Protestants and we shall rule in Ireland. -But thank God! in that they were disappointed, and Protestantism yet lives in the land of my fathers, and is, wherever it exists, the stronghold of freedom. Now, passages are cheap, and the Catholic interest and prospect of ruling in Europe is almost extinguished, and the Church is using all her means to throw over her minions, hoping to impose themselves upon the unsuspecting American people, and gradually undermine our liberties. But they crowed too soon—their evil machinations are become so plain that their real object can no longer be hidden, and if the great American people do not now rebuke them they must be recreant to the principles of liberty dearly bought by the blood of a noble ancestry;—andklmigbtv nerve them for the battle!ay God T ou wiinquire what remedy I would propose. First, I would so alterthe Naturalization Laws that not one of them should ever become a citizen; and if we can not discriminate between them and the Protestant emigrant*, let them all stand on the same footing—they will not make the fortieth part of the Papist emigration. And when they understand the matter they will not complain, for they all know the Papal Church so well that they believe if she should gain theascendancy it would be the death knell of liberty. in the second place I would bury therotten carcass of old Democracy head downward, so deep that every struggle to rise wouplace it farther and farther beyond the pow of resurrection. I remain your affectiona father. WILLIAM FLYNN.