In 1833 Simpson became a member of the Royal Medical and Physical Societies of Edinburgh. Of the former he was soon President. A writer in the _Scotsman_ for May 10, 1870, thus described his appearance in that capacity. After speaking of his long tangled hair, and very large head, he says: “A poet has since described him as one of ‘leonine aspect.’ Not such do we remember him. A pale, large, rather flattish face, massive, brent brows, from under which shone eyes now piercing as it were to your inmost soul, now melting into almost feminine tenderness, and coarsish nose, with dilated nostrils, a finely-chiselled mouth, which seemed the most expressive feature of the face, and capable of being made at will the exponent of every passion and emotion. Who could describe that smile? When even the sun has tried it he has failed, and yet who can recall those features and not realise it as it played round the delicate lines of the upper lip, where firmness was strangely blended with other and apparently opposing qualities? Then his peculiar, rounded, soft body and limbs, as if he had retained the infantile form in adolescence, presented a _tout ensemble_ which even had we never seen it again would have remained indelibly impressed on our memory.” In 1832 Alexander and Mary Simpson both married. Alexander’s wife, however, became as attached as his sister to James, and there was no interruption to the family helpfulness. When cholera appeared in Bathgate, Alexander made a will securing a provision for James if he died. “I trust,” wrote this true brother, “every one of you will look to him. But I dare say every one of you has a pleasure in doing him good by stealth, as I have had myself.” The brothers Alexander and John enabled James to visit London and the Continent in 1835 to see a variety of practice; his travelling companion was Dr. Douglas Maclagan, afterwards Professor of Medical Jurisprudence at Edinburgh. On his return Simpson gained some practice, but chiefly among those who could pay him little or nothing. In May 1836 he obtained the situation of house-surgeon to the Lying-in Hospital, which he held for a year. This soon led to an increase of practice among better-paying patients. He now gave some courses of lectures on Midwifery in the Extra-Academical School, which were well received, besides being appointed interim lecturer on Pathology, when his friend Dr. Thomson had resigned. He gave great labour to the preparation of his lectures, besides continuing to publish original papers on Midwifery. At this time he rose repeatedly at three in the morning, when he did not sit up all night. But with all his work he found time for social enjoyment, for family interests, for messages to old schoolfellows in humble life.