Cases dependent upon malignant growths within the cranium are absolutely beyond the reach of treatment. Paralysis dependent upon bony tumors, even though they are benign in character, are also for the most part beyond the reach of surgical interference. If the paralysis is complete--that is, if all the muscles are involved--there are no indications for any operative procedure. If, however, only the nerves that supply the posterior crico-arytenoids are involved, as occasionally happens, tracheotomy should be resorted to even though the dyspnoea is not urgent. This operation places the patient in a condition of temporary safety, and gives time to resort to other means if the indications for their use can be found. The second group of cases includes all those in which the cause of the paralysis is due to the presence of disease of the nerve-trunks, or to pressure upon the nerves between their emergence from the cranium and their terminations in the muscles of the larynx. Malignant growths and benign tumors situated along the tract of the nerves, and pinching them, are readily recognized, and when not contraindicated by other facts they should be removed. Enlargement of the thyroid gland may in some cases press upon the nerve and cause paralysis. This is occasionally relieved by appropriate treatment directed to it. Among those means which have occasionally been found efficacious for this purpose iodine or some of its compounds, and especially electricity in the form of galvanism, seem to be entitled to the most confidence. For paralysis dependent upon cicatricial pinching of the recurrent nerve-trunks relief may possibly be obtained by dissecting out the bands by which the nerves are compressed. This is hardly indicated for the partial derangements which do not endanger life, as in unilateral paralysis of the recurrent. Where the trunk of the nerve is entirely obliterated nothing can be done, and in many cases of injuries along the trunk of the recurrent it will be impossible to know that the nerve has not been destroyed in the mechanical lesion. Paralysis caused by pressure upon the intra-thoracic portion of nerve is beyond the reach of surgical interference. When this is aneurism, disease of the apex of the lung, or pleuritis, as may possibly happen, the paralysis or paresis must of course have a history coeval with the thoracic disease. The causes themselves are unfortunately persistent and tend to terminate in death; the paralyses are therefore persistent and beyond the reach of medical or surgical relief. In cases where the posterior crico-arytenoids are especially involved, tracheotomy, as in the same condition from intra-cranial disease, should be performed. It is certainly true that there may be a morbid {90} condition of one or both of the pneumogastrics or recurrent nerves without macroscopic changes in their structure; in such cases the use of the faradic current together with general tonics is indicated.