Abstract
IT MUST now be about 20 years since my teacher and friend George Barger spoke in this Institution on the early work on the chemistry of throxine which had been done in my laboratory and in which he and I had been associated. When I received the honour of an invitation to deliver this Richardson Lecture, it seemed to me appropriate that I should use the occasion for a review of the progress of work on the thyroid problem from the point where Barger left off. Naturally I shall treat the subject almost entirely from the biochemical point of view, for it is this aspect of the work with which I have been partly concerned and which I have followed most closely; also I must begin my story a little earlier than the date that I have mentioned. The discovery of thyroxine by Kendall in 1915, followed a little more than ten years later by the elucidation of its chemical constitution and by its synthesis (Harington, 1926; Harington and Barger, 1927),