8 IXTR OD UCTO R Y 



part of the writer of these sheets, would probably 

 destroy that confidence which it is his wish to inspire ; 

 where writers differ, it will be his aim to select the 

 opinions and practice best supported by facts, and the 

 plain principles of common sense: in stating those 

 opinions and facts, he will sometimes adopt the lan- 

 guage of others, in preference to any form of expres- 

 sion he might be able to devise. As the great ob- 

 ject of the writer is, to be useful to those who require 

 information it will be his aim to be correct, rather 

 than scientifick, in order that he may be better un- 

 derstood. 



