We have been surprised with one of the most extraordinary phenomena in the moral world, which, I dare say, has happened in the course of this half century. We have had a party of Presbytery relief, as they call themselves, for some time in this country. A pretty thriving society of them has been in the burgh of Irvine for some years past, till about two years ago a Mrs. Buchan from Glasgow came among them, and began to spread some fanatical notions of religion among them, and in a short time made many converts; and among others their preacher, Mr. Whyte, who, upon that account, has been suspended and formally deposed by his brethren. He continued, however, to preach in private to his party, and was supported, both he, and their spiritual mother, as they affect to call old Buchan, by the contributions of the rest, several of whom were in good circumstances; till, in spring last, the populace rose and mobbed Mrs. Buchan, and put her out of the town; on which all her followers voluntarily quitted the place likewise, and with such precipitation that many of them never shut their doors behind them; one left a washing on the green, another a cow bellowing at the crib without food or anybody to mind her, and after several stages they are fixed at present in the neighbourhood of Dumfries. Their tenets are a strange jumble of enthusiastic jargon; among others, she pretends to give them the Holy Ghost by breathing on them, which she does with postures and practices that are scandalously indecent; they have likewise disposed of all their effects, and hold a community of goods, and live nearly an idle life, carrying on a great farce of pretended devotion in barns and woods, where they lodge and lie all together, and hold likewise a community of women, as it is another of their tenets that they can commit no moral sin. I am personally acquainted with most of them, and I can assure you the above mentioned are facts. This, my dear Sir, is one of the many instances of the folly of leaving the guidance of sound reason and common sense in matters of religion. Whenever we neglect or despise these sacred monitors, the whimsical notions of a perturbated brain are taken for the immediate influences of the Deity, and the wildest fanaticism, and the most inconsistent absurdities, will meet with abetters and converts. Nay, I have often thought, that the more out-of-the-way and ridiculous the fancies are, if once they are sanctified under the sacred name of religion, the unhappy mistaken votaries are the more firmly glued to them. I expect to hear from you soon, and I beg you will remember me to all friends, and believe me to be, my dear Sir, your affectionate cousin, ROBERT BURNESS. P.S.--Direct to me at Mossgiel, parish of Mauchline, near Kilmarnock. [Footnote 6a: Probably John Caird, junior, as the father would be over sixty if he was about his wife's age, and she, Elspat Burnes, was born, we know, in 1725.] * * * * *