Dr. O'Dwyer's originality in the invention of intubation has sometimes been doubted. The idea of some such instrumental procedure as he finally perfected seems to have occurred to practitioners of medicine a number of times in medical history. No one reduced the idea to practice in any successful degree. O'Dwyer's invention was not some chance hit of good fortune in lighting on a brilliant idea, but the result of years of patient investigation and shaping of means to ends. Often failure seemed inevitable, but he continued to experiment until he forced the hand of the goddess of invention to be favorable to him. The history of intubation is interesting mainly because it brings out clearly O'Dwyer's success where others had failed. The evolution of intubation forms, moreover, a very interesting chapter in the story of medicine. It is curious to learn that the Greeks of the classical period, and very probably for a long time before, knew something of the possibility of putting a tube into the larynx in cases of stenoses or contractions which threatened to prevent breathing. It is clear that they thus secured patency of the air-passages after these had become occluded. Hippocrates mentions {336} canalization of the air-passages, and suggests that in inflammatory croup with difficulty of respiration, canulas should be carried into the throat along the jaws so that air could be drawn into the lungs. This is probably diphtheria, the first mention of the disease in medical literature, though it is usually said to have been first described in Spain at the beginning of the nineteenth century. There is evidence, too, in Greek medical history that these directions were followed by many practising physicians of those early times. Considering that intubation of the larynx is usually thought to be a very modern treatment, this tradition in Greek medical history serves to show how transitory may be the effect of real progress in applied science. After a time the Asclepiades, and some centuries later Paulinus of AEginetus, rejected the teaching of Hippocrates in this matter, while the latter suggested even the employment of bronchotomy.