IV PREFACE. 



species of regular confusion might not have 

 suited a majority of readers, and would at the 

 same time have increased the difficulty of refe- 

 rence, he has thought it preferable to distribute 

 them under certain general heads, but without 

 any particular anxiety as to their being strictly 

 within the legitimate boundaries of the science 

 designated. 



The sources from which a considerable por- 

 tion of these Notes are derived will be easily 

 recognized, although some have been re-con- 

 structed to keep pace with the progress of dis- 

 covery, and others modified to suit the compiler's 

 own view of the subject. But all pretensions 

 to originality are disclaimed, the grand object 

 having been to condense and simplify from 

 every source such useful and interesting facts 

 and principles as are likely to adhere to the 

 memory of even the most careless reader, and 

 to which, like points of departure in navigation, 

 he might when at a loss appeal for correction. 

 The intellectual faculties, being thus called into 

 action by a single effort, are likely to exert a 

 much more energetic vigour of reflection, than 

 if intercepted by a prolix commentary or ver- 

 bose illustration, and many who, like the 



