Studies on the Velocity of Blood Flow

This paper presents the first measurements of the velocity of blood flow through the lungs of man.Thorough understanding of the blood flow through the lungs is of great significance in understanding adapta- tions of the circulation in health and disease.The study of the pulmonary circulation has, therefore, always at- tracted the interest of investigators.The literature is voluminous and was reviewed in 1903 by Tigerstedt (1) and in 1921 by Wiggers (2).In animals the study of the pulmonary circulation necessitates such distortion of the normal physiological conditions that interpre- tation of the results is diflicult.The chest has usually been opened, the negative intrathoracic pressure abolished, and normal inspiration has been replaced by forcible distention of the lungs with positive blasts of air.