Astley Cooper’s activities were at this time strongly directed towards the improvement of his profession by intercourse and discussion at societies, of several of which he was the life and soul. The Physical Society at Guy’s Hospital afforded his earliest opportunity of this kind, and long retained his active interest. During his short stay at Edinburgh his predominance was so evident that he was chosen president of a society to protect students’ rights against usurpations by the professors. Here also he joined a Speculative Society, and read a paper in favour of the Berkeleian theory of matter. One of the debates which he opened was on the subject “Is man a free agent?” He would have been a president of the Royal Medical Society at Edinburgh had he returned for a second winter, so much did he distinguish himself in debate. At a later period the strength of his association with Edinburgh was attested by his forming the Edinburgh Club in London for former Edinburgh medical students. The most important society, however, with the foundation of which he was connected, was the Royal Medical Chirurgical Society, which originated in a secession from the Medical Society of London. Dr. Yelloly, who was intimately connected with the new foundation, says of Mr. Cooper at this time: “I never saw any one more open-hearted as a companion, more unreserved in his remarks, with always a large store of information at his command, and who was at the same time more kindly disposed, and abounding in all sorts of material for the gratification of those with whom he associated. He was not a reading man; but he contrived to get the most valuable information of every description, whether professional or general, and always to use it in the best, the most attractive, and the readiest way.” The treasurer of the society was Astley Cooper, and he rendered essential service. The earliest volume of its Transactions, published in 1809, contained a paper recording his first operation for the relief of aneurism of the carotid artery by tying it below the aneurism—a method now established. But he had previously published (part 1 in 1804, part 2 in 1807) a work which largely contributed to his reputation, namely, on Hernia or Rupture. A second edition was published in 1827. The anatomical structures concerned were excellently expounded and illustrated, and the experience gained in frequently and successfully operating in cases of this disease gave Mr. Cooper a position of the highest authority. As so often happens to medical men, his attention was especially called to this disease from the fact that he had been subject to it from early life. The anatomical study he undertook in order to perfect his knowledge of this matter was immense. “I have related no case,” he says, “and given no remark, for the truth of which I cannot vouch.” When his pupils showed him some interesting appearance in a dissection, he would say; “That is the way, sir, to learn your profession. Look