After his publication of the article on "The Permanent Patency of the Mouth of the Aorta," or "Inadequacy of the Aortic Valves," he at once became recognized as one of the best clinicians in the city. This article appeared, in April, 1832, in the _Edinburgh Medical and Surgical Journal_, at a time when, as has been said, its author was not yet thirty years of age. As soon as he began his work at the Jervis Street Hospital, he gave a course of lectures, and as he was an excellent talker and a good demonstrator, he at once attracted a large class. In 1834 he joined Hargrave's School, in Digges Street, Dublin, as lecturer on the practice of medicine, and continued to hold the position for more than ten years. His success as a lecturer attracted many students from the other medical schools. Corrigan's class was often three times as large as that of other medical lecturers in the city. It not infrequently happened that as a result of his {209} popularity the medical class was two or even three times as large as the surgical and anatomical classes at the same institution. This was very unusual, for Dublin was famous for its anatomical instruction, and there were often five times as many pupils enrolled in the anatomy classes as in the medical classes. It was not long before honors began to be showered upon Corrigan. When he was about forty the diploma of the London College of Surgeons was conferred upon him, and, as according to the by-laws of the institution the diploma can only be conferred after examination, Corrigan's examination was made to consist of the reading of the thesis, "Inadequacy of the Aortic Valves," before the faculty and the other members of the college. In 1849 the University of Dublin conferred upon him the degree of M.D., _honoris causa_. There was only one setback in Corrigan's medical career in Dublin. When first proposed for honorary fellowship in the Irish College of Physicians, he was rejected. The reason was entirely apart from medical matters. Corrigan was the most active member of the Irish Board of Health, which had charge of the famine cases in Ireland, during the awful years between 1845 and 1850. This Board proposed to allow about five shillings per day to physicians who would be sent to the country to attend famine fever cases. It is easy to understand that this remuneration was considered inadequate and the Board's decision in the matter raised a storm of protest. Graves wrote very bitterly with regard to it, and blamed Corrigan for any part he might have had in it. The result was that for some time Dr. Corrigan was the most popularly hated physician in the medical profession of Dublin.