&34 -A ConjeBure concerning 
Art. ii. It is evident, that while x increafes from be- 
ing equal to s/ q ad infinitum , both the quantities x % and 
qx will increafe ad infinitum likewife. But it does not 
therefore follow, that the excefs of x 3 above qx will con- 
tinually increafe at the fame time. This will depend 
upon the relation of the contemporary increments of 
x 3 and qx: if the increment of x 3 in any given time is 
equal to the contemporary increment of qx, the com- 
pound quantity x 3 —qx will neither increafe nor decreafe, 
but continue always of the fame magnitude during the 
faid time, notwithftanding the increafe of x ; if the for- 
mer increment is lefs than the latter, the faid compound 
quantity will decreafe ; and, if it is greater, it will in- 
creafe. We muft therefore inquire, whether the incre- 
ment of x 3 in any given time is greater or lefs than the 
contemporary increment of qx. 
Art. 1 2 ( Now, if x be put for the increment which x 
receive? v n any given time, the increment of x 3 in the 
fame time will be the excefs of x+x\ 3 above x 3 , that is, 
the excefs of x 3 + ^x l x + x 3 above x 3 ; and the in- 
crement of qx in the fame time will be the excefs of 
q x x+x, or ,qx+qx, above qx; that is, the increment of x % 
will be $x , 'x+ 3xi 2 +x 3 , and that of qx will b eqx. Now in 
the equation# 3 — <7;v=rit is evident, that xx mull; be greater 
than q; for otherwife x 3 would not be greater than qx, 
as 
