vi PHYSIOLOGY 



outlines of the history of each branch of the subject, but does not 

 allow this to interfere with the even flow of narration. 



It is natural that writers of Text-books should make frequent 

 reference to the work that has been done by their own country- 

 men. Italian work is less widely known than it deserves, and 

 one of the advantages of this book for English-speaking folk is 

 that Italian workers receive their meed of notice. It will, how- 

 ever, be a shock to many English readers to find that Professor 

 Luciani allots the discovery of the systemic circulation of the 

 blood to his countryman, Cesalpinus. That the circulation of the 

 blood was described and demonstrated by Harvey, no one doubts. 

 That there were a number of forerunners of Harvey who under- 

 stood this or that important fact connected with the circulation is 

 equally undoubted. In considering the place to be assigned to 

 each of those who helped to solve the problem, two separate 

 questions arise. First, How far are the facts and views original 

 and not obtained from unacknowledged sources ? and secondly, 

 What was the exact degree of understanding of the subject 

 possessed by each writer ? It may seem that the former question 

 only would be difficult to solve. In fact, the difficulty of the 

 latter is no less, or at any rate differences of opinion with regard 

 to it have not been less ardent ; and so we find that whilst most 

 authorities regard Cesalpinus as having but imperfectly compre- 

 hended the systemic circulation, and to have seen it " darkly 

 through Galenical glasses," some, as Professor Luciani, consider 

 that his comprehension was whole and without flaw. 



Finally, it may be noted that the Editor, Dr. Camis, has 

 added at the end of each chapter a selected list of English-written 

 Monographs and Papers, and thus has put the student who 

 knows no other language than English in the way of obtaining 

 a fuller knowledge of any branch of Physiology in which he may 

 be interested. 



J. N. LANGLEY. 



CAMBRIDGE, Jan. 1911. 



