from 1757 he delivered lectures on clinical medicine in the edinburgh royal infirmary. on the death of charles alston in 1760, cullen at the request of the students undertook to finish his course of lectures on "materia medica"; he delivered an entirely new course, notes of which were published in an unauthorised edition in 1771, but which he re-wrote and issued as "a treatise on materia medica" in 1789.