TRACTS ON VARIOUS SUBJECTS, Sec. 145 



vated without one or the other : but as I have before observed, 

 they must be carefully made upon perfectly horizontal lines ; 

 for if these furrovi^s or belts, were to deviate from a true level, 

 they would operate as drains and carry off the water : and thereby 

 defeat the very purpose for which they are intended. 



24th September, 1812. 



U 



