CHAPTER VII.

THE CIRCULATION 101

_The Blood--Its Plasma and Corpuscles--Coagulation of the Blood--The Uses of the Blood--Transfusion--Change of Color--The Organs of the Circulation--The Heart, Arteries, and Veins--The Cavities and Valves of the Heart--Its Vital Energy--Passage of the Blood through the Heart--The Frequency and Activity of its Movements--The Pulse--The Sphygmograph--The Capillary Blood-vessels--The Rate of the Circulation--Assimilation--Injuries to the Blood-vessels._