Injection of the tympanum as a method of treatment in deafness was first suggested and used by Gray1 in 1934 at the Middlesex Hospital in London. Gray advocated this type of therapy for otosclerosis. He employed thyroxin as the medium of injection. However, his choice of thyroxin was made on an empiric basis. Although there is some evidence to indicate that hereditary endocrine dysfunction of the thyroid gland is present with otosclerosis, thyroxin was not selected primarily for this reason. Gray's first purpose was to find an agent which when applied locally would produce active congestion of the blood vessels in the tympanum and at the same time be free from any qualities which might cause an inflammatory reaction. The basis of thyroxin therapy, as explained by Gray in his views on the cause of otosclerosis, was to stimulate circulation in the organ of hearing through active congestion of the