[ 5*9 ] 
But for this end, where commodious principles do 
not readily offer themfelves, the moff general means 
is to confider firft fimple cafes of the problem in 
queffion, and from thence to proceed gradually to 
the more complex, as has been here done in the pre- 
fent problem, where the feveral preceding cafes lead 
one after another to the points and lines required for 
the laft cafe, wherein the problem is ffated in its moff 
extenfive form. 
< 
INDEX. 
