VI TREFACE. 



and Avliovo not original, liuvo boiMi faith fully copied or ro- 

 duood iVoni tlio various works (|iiotod. For iho liguros of 

 the sludls, rooonrso has boon had in almost OYory instnuoe 

 to the objoots themselves. 



Octoht-r, 1858. 



