PREFACE. vil 



Keeping in mind that our primary object should be 

 to afford the most effective aid to the student, the body 

 of materials has been enlarged and improved upon with 

 judicious additions, new illustrations, and biographical 

 quotations. We have endeavored to meet the want 

 expressed in a recent review of a distinguished work on 

 Physiology, that of " a well-digested text-book of Phy- 

 siology adapted to the wants of the advanced student, 

 *which is still a desideratum in American scientific liter- 

 ature If the foreign books upon any subject are 



more meritorious than those of our own country, the 

 preference for them is naturally and rightly exercised. 

 For science is cosmopolitan ; and the student consults 

 his own interests and that of science at large by supply- 

 ing himself with the most useful text-books, no matter 

 what may be their nationality." In brief, we have 

 made every effort, within the limits assigned us by the 

 original plan, to lay before the student (and the physi- 

 cian whose time will not allow a prolonged study of 

 more extensive works) a satisfactory treatise on Physi- 

 ology in its present stage. 



LONGWOOD, January, 1875. 



