Induced paralysis of the diaphragm by cervical phrenicotomy as a method of treatment of certain severe chronic pulmonary lesions was first suggested by Stuertz1 in 1911. The proposal of Stuertz followed experimental work of Senac, Arnemann, Purkinje, Budge and Gerhardt,2 and was made on the basis that the diseased lung would be helped in the sense of collapse therapy by immobilization and compression of the diseased tissue. In 1912, Hellin3 differed from this view and maintained that the diaphragm never becomes actually immobilized. He stated that each half of the diaphragm is innervated not only by the corresponding phrenic nerve, but by bundles arising from the intercostal nerves, and that the phrenic nerves anastomose with each other. After experimental work on guinea-pigs, rabbits and dogs, he stated that section of the phrenic nerve does not always cause paralysis of the diaphragm. Therapeutic paralysis of the diaphragm was