PREFACE TO THE SECOND EDITION. 



In presenting to the public the present stereotype edi- 

 tion of this work, it is proper to state, that no labor or 

 expense has been spared to render it still more worthy 

 of the kind approbation with which it has been received. 

 A large proportion of it has been entirely re-written, 

 many corrections have been made, and numerous and 

 highly valuable illustrations introduced ; these improve- 

 ments, together with the questions at the end of each 

 chapter, cannot but render the work better adapted to 

 the objects for which it was written. 



The author flatters himself that this treatise will be 

 found to contain the substance of what is yet known on 

 the subject of Human Physiology, and most that is 

 valuable, which is scattered through many learned and 

 ponderous volumes. In preparing it, more than fifty 

 different works have been consulted, from all of which 

 the author has freely taken whatever he found adapted 

 to his purpose. Originality has not been aimed at, as it 

 was precluded by the very nature of the subject ; in- 

 deed it would have been unsuited to the object in view. 



