Page:The Harveian oration, 1873.djvu/16

 been able to prove it.' The fact that Harvey performed experiments in the way of injection may be unknown to many persons who are too well informed to conceive that the arteries may or can, compatibly with the carrying on of any circulation, contain air in an uncombined state; for these experiments are not to be found recorded either in the treatise De Motu Cordis or in either of the two letters to Riolanus; which two compositions were, in the older editions of Harvey's works, printed as three parts of a single treatise, under the names of ' Exer-citatio Anatomica i. De Motu Cordis, etc.,'Exercitatio Anatomica ii. De Circulatione Sanguinis,' and 'Exercitatio Anatomica iii. De Circulatione Sanguinis'; and were, till the appearance of the College of Physicians' edition in 1 766, the only published, as they