In the _Recollections of John O'Keefe_, the following anecdote is related:--
"In 1775 I was in company with Father O'Leary, at the house of Flynn, the printer in Cork. O'Leary had a fine smooth brogue; his learning was extensive, and his wit brilliant. He was tall and thin, with, a long, pale, and pleasant visage, smiling and expressive. His dress was an entire suit of brown, of the old shape; a narrow stock, tight about his neck; his wig amply powdered, with a high poking foretop. In the year, 1791, my son Tottenham and I met him in St. James's Park, (London,) at the narrow entrance near Spring Gardens. A few minutes after, we were joined accidentally by Jemmy Wilder, well known in Dublin--once the famous Macheath, in Smock Alley--a worthy and respectable character, of a fine, bold, athletic figure, but violent and extravagant in his mode of acting. He had quitted the stage, and commenced picture-dealer; and when we met him in the Park, was running after a man, who, he said, had bought a picture of Rubens for three shillings and sixpence at a broker's stall in Drury-lane, and which was to make his (Wilder's) fortune. Our loud laughing at O'Leary's jokes, and his Irish brogue, and our stopping up the pathway, which is here very narrow, brought a crowd about us. O'Leary was very fond of the drama, and delighted in the company of the 'Glorious Boys,' as he called the actors--particularly that of Johnny Johnstone, for his fine singing in a room."
On the 26th February, 1782, the following interesting debate took place, the subject under consideration being a clause in the Catholic Bill directed against the friars:--
"Sir Lucius O'Brien said, he did not approve of the regulars, though his candor must acknowledge that many men amongst them have displayed great abilities. Ganganelli (Clement XIV) and the Reverend Doctor Arthur O'Leary are distinguished among the Franciscans; and many great men have been produced in the Benedictine order. He saw no temptation that regulars had for coming here, if it was not to abandon certain competence where they were, for certain poverty in this kingdom.
"Mr. Grattan said, he could not hear the name of Father O'Leary mentioned without paying him that tribute of acknowledgment so justly due to his merit. At the time that this very man lay under the censure of a law which, in his own country, made him subject to transportation or death, from religious distinctions; and at the time that a prince of his own religion threatened this country with an invasion, this respectable character took up his pen, and unsolicited, and without a motive but that of real patriotism, to urge his own communion to a disposition of peace, and to support the law which had sentenced him to transportation. A man of learning--a philosopher--a Franciscan--did the most eminent service to his country in the hour of its greatest danger. He brought out a publication that would do honor to the most celebrated name. The whole kingdom must bear witness to its effect, by the reception they gave it. Poor in everything but genius and philosophy, he had no property at stake, no family to fear for; but descending from the contemplation of wisdom, and abandoning the ornaments of fancy, he humanely undertook the task of conveying duty and instruction to the lowest class of the people. If I did not know him (continued Mr. Grattan) to be a Christian clergyman, I should suppose him by his works to be a philosopher of the Augustine age. The regulars are a harmless body of men, and should not be disturbed.