Stokes, most prominent of the Irish school of medicine, established his reputation by his book on diseases of the chest. Important among its contents are his discovery of a stage of pneumonia prior to that described by Laennec as the first, his observations that contraction of the side has sometimes followed the cure of pneumonia and that paralysis of the intercostal muscles and diaphragm may result from pleurisy, and his employment of the stethoscope as an aid to the detection of foreign bodies in the air passages.