Continuous Respiration without Respiratory Movements

The object of the function of respiration is to supply the animal with oxygen and to remove carbon dioxide. To attain this object the vertebrates are provided with a complicated mechanism of which the respiratory movements are an essential feature. The respiration appears as a continuous chain of rhythmically recurring cycles, each cycle consisting of two antagonistic movements, one which carries air into the body and the other which assists its removal from the body. When the muscular activity of the body is eliminated by one cause or other and the exchange of the gases is carried on by so-called artificial respiration, again the respiration is rhythmically discontinuous and each cycle is composed of the two antagonistic movements: the inflow of air is carried on rhythmically by some external mechanism, while the return of the air is accomplished during the intermission by the elastic forces of the body. The rhythmic antagonistic movements seem thus to be inseparable from the function of respiration. In studying recently the nature of the mechanism of the respiration in the presence of a double pneumothorax, while the animal is breathing compressed air by the Brauer method of overpressure, we discovered the fact that under certain conditions respiration can be carried on by continuous inflation of the lungs, and without any normal or artificial rhythmical respiratory movements whatever. This observation was verified by many experiments and we will describe here briefly the essential features of the experiment. A longitudinal slit is made in the trachea of an anesthetized dog or rabbit and a glass tube introduced down to the tracheal bifurca-