PREFACE. 



To deliver a System of the Doctrines and Rules proper for 

 directing the Practice of Physic, is an undertaking that appears 

 to me to be attended with great difficulty ; and, after an ex- 

 perience of more than forty years in that practice, as well as 

 after much reading and reflection, it was with great diffidence 

 that I ever entered upon such a work. It was, however, what 

 seemed to be my duty as a professor, that induced me to make 

 the attempt ; and I was engaged in it by the same sentiments 

 that the illustrious Dr. Boerhaave has expressed in the following 

 passage of the Preface to his Institutions : ' Simul enim docendo 

 admotus eram sensi, propriorum cogitatorum explicatione do- 

 centem plus proficere, quam si opus ab alio conscriptum inter- 

 pretari suscipit. Sua quippe optime intelligit, sua cuique prae 

 caeteris placent, unde clarior fere doctrina, atque animata ple- 

 rumque sequitur oratio. Qui vero sensa alterius exponit, infeli- 

 cius saepenumero eadem assequitur ; quumque suo quisque 

 sensu abundat, multa refutanda frequenter invenit, unde gravem 

 frustra laborem aggravat, minusque incitata dictione utitur.' It 

 is well known, that a text-book is not only extremely useful, but 

 necessary to students who are to hear lectures : and from the 

 same considerations that moved Dr. Boerhaave, I also wished to 



