ACCORDING to the author it is the ‘transmyringal’ portion of the chorda tympani nerve which in practice remains exposed to the cold atmospheric air and triggers the pathologic process involved in Bell's palsy, affecting the facial nerve secondarily, rather than a primary condition of the facial nerve. This theory was proved by creating a Bell's palsy (paralysis a frigore) with cold-air-stimuli to the tympanic membrane in experimental animals (two monkeys). On the basis of this observation the author recommends ‘medical decompression’ of the facial nerve by means of infra-red fomentation of the drum, and eustachian insufflation of hydrocortisone, in cases of Bell's palsy before retrograde extension of oedema from the chorda tympani to the facial nerve can cause irreversible damage. Subsequently, the author has successfully managed fourteen cases (93.4 per cent) of Bell's palsy with a definite history of exposure to cold (paralysis a frigore). It is suggested that the ear canal be plugged with cotton as a preventive measure; and that chorda tympani neurectomy be performed to eliminate the chances of recurrence of the disease in cases of recurrent Bell's palsy.