A correspondent of the Pittsburgh Witness, detailing the particulars of an Anti-Slavery meeting in Washington co. Pennsylvania, says:-- ‘After Dr. Lemoyne, the President of the Pennsylvania Anti-Slavery Society, had finished his address, in which the principles and measures of the Anti-Slavery Society were fully exhibited, the Rev. Charles Stewart, of Kentucky, a slaveholding clergyman of the Presbyterian church, who was casually present, rose and addressed the audience, and instead of opposing our principles as might have been expected, fully endorsed every thing that had been said, declaring his conviction that such a speech would have been well received by the truly religious part of the community in which he resided, and would have been opposed only by those who were actuated by party politics alone, or those who ‘neither feared God nor regarded man.’ I give thee now a letter from a gentleman in a South Western slaveholding State, to J. G. BIRNEY. ‘_Very Dear Sir_:--I knew you in the days of your prosperity at the South, though you will not recognize me. Ever since you first took your stand in defence of _natural rights_, I have been looking upon you with intense interest. I _was_ violently opposed to Abolitionists, and verily thought I was doing service to both church and State, in decrying them as _incendiaries_ and _fanatics_. What blindness and infatuation! Yet I was _sincere_. Ah! my dear sir, God in mercy has taught me that something more than _sincerity_, in the common acceptation of the term, is necessary to preserve our understandings from idiocy, and our hearts from utter ruin. How could I have been such a _madman_, as coolly and composedly to place my foot upon the necks of immortal beings, and from that horrid point of elevation, hurl the deep curses of church and State at the heads of----whom? Fanatics? No, sir!--_but of the only persons on the face of the earth, who had HEART enough to FEEL, and SOUL enough to ACT, in behalf of the RIGHTS OF MAN_! Yet I was just such a madman! Yes, sir, I was a _fanatic_, and an _incendiary_ too--setting on fire the worst passions of our fallen nature. But I have repented. I have become a convert to political, and I trust, also, to _Christian Freedom_. The spectacle exhibited by yourself, and your compatriots and fellow-christians, has completely overcome me. Your reasonings convince my judgment, and your ACTIONS win my heart. God speed you in your work of love! The hopes of the world depend, under God, upon the success of your cause. Very respectfully and with undying affection, Your friend and brother, A SOUTHERNER.’ Another of J. G. Birney’s southern correspondents says, in 1836,