Thomas was not yet twelve, when, with his brother William, he was sent on to the University of St. Andrews. At such an age, common enough then in Scotland, boys were incapable of grasping the great aims of a university; and college to them was but an upper school. But the change to the university had at first no effect in mending the idle ways of our student. He was ’volatile, boyish, and idle.’ Yet, even from the first, he was noted for strict integrity and warm affection, and in all that he did undertake he was enthusiastic and persevering. It was not till his third session that he became attached to any branch of learning. The science that captivated him then was mathematics. And so ardently did he devote himself to it, that long afterwards, about the time when he left Kilmany, he was familiarly known as ’Mr. Chalmers, the mathematician.’ He might have borne the designation to the very end. His mind was fashioned on the mathematical model, taking its stand on realities, the substantial verities of life; striving to explain their relations and applications, and then pressing them with tremendous energy on the hearts and consciences of his fellows. For Professor Brown, his mathematical teacher, he retained through life the warmest regard; and when he died in 1836, he wrote to his widow, that of all his public instructors he was the one that impressed him most, and to whom he owed most in the formation of his tastes and habits, and in the guidance of his literary life. As the termination of his curriculum in arts drew near, it became necessary that he should choose a profession. Strange to say, although he had no favour either for theology or religion, he had declared from his boyhood for the ministry. Some of the more picturesque sayings of the Bible had taken a remarkable hold of his mind. When but three years old, being missed and sought for, after it had become dark, he was found alone, pacing up and down in the nursery, repeating to himself the words of David, ’O my son Absalom, my son Absalom; O Absalom, my son, my son!’ The sister of one of his schoolfellows used to tell of her breaking in on the two, and finding him on a chair, preaching vigorously to his single hearer. It was the soul of the orator asserting itself from the very first.