Facial Palsy (Bell's Palsy). This is one of the commonest forms of local paralysis affecting a special motor nerve, viz. the seventh cranial nerve, or facial nerve. The following are the symptoms of the affection: - The muscles of the face on the paralysed side cannot be put in action by an effort of the will, and, moreover, they no longer present the condition of tonic contraction which is natural to them in the normal state apart from their being specially called into play. Thus the natural lines of expression are lost, the naso-labial groove is obliterated, the mouth is drawn upwards on the unaffected side, and the furrows on the forehead are less marked on the paralysed side. The condition of things becomes plainly manifest when the patient attempts to laugh, to close his eyes, to frown, and the like. Bell's palsy may be due to disease of the facial nerve, originating in any part of its course. It is most commonly produced by exposure to cold, or it may arise as a complication of ear disease (the nerve in its course through the temporal bone being specially exposed to involvement where aural mischief is present).