Throughout the entire series of experiments with both the portable respiration apparatus and the respiratory-valve apparatus, the respiration rate was obtained graphically by means of a pneumograph placed around the chest of the subject. Certain respiration rates were likewise determined on the morning of the standing respiration experiments prior to walking by noting the rise and fall of the spirometer bell. These were counted in definite periods of time and were recorded by the observer. All the respiration rates observed in this series of experiments were obtained when the subject was attached to some form of breathing appliance. With the portable respiration apparatus, for both the lying and the standing positions, the regulation mouthpiece and nose-clip were used. With the respiratory-valve apparatus a mask was attached to the face; with this, in all probability, a more normal respiration was obtained. Although it was the opinion of the observers that relatively slight, if any, changes in respiration rate were apparent throughout the entire series of tests, we have had all these records carefully inspected and counted and the values obtained on the different mornings are presented in table 108. Since the respiration rate likewise has specific value in the computation of the alveolar air and the amount of air expired per respiration, certain respiration rates also appear in table 111. (See p. 480).