Secondary Planet, againft which we were before deputing : ) 
But by the Common Center of Gravity of the Bodies pEarth and Moon, 
as one Aggregate. 
Now fuppofing ABC D E to be a part of the See Fig. 
great Orb of the Annual motion, defcribed by the 2, and 3* 
Common Center of Gravity, in fo long time as from a Pull-Moon 
at A to the next New-IUcon at E» ( which, though an Arch 
of a Circle or Ellipse , whofc Center we fuppofe at a due diftance 
below it; yet being but about of the whole, may well e- 
nough be here reprefented by a ftreight Line : ) the Center of 
the Earth at T, and that of the Moon at L, mu ft each of them 
( fuppofing their common Center of Gravity to keep the Line 
A E) be fuppofed to deferibe a Periphery about that Com- 
mon Center, as the Moon deferibes her Line of -Menfirual mo- 
tion. ( OF which I Lave ( in the Scheme ) onely drawn that 
of the Earth 5 as being fufficient tp our prefent purpofe; paral- 
lel to which, if need be. we may fuppofe one deferibea by the 
Moon ; whofe diftance is aifo to be fuppofed much greater 
from X than in the figure is expreffed, or was neeeffary to ex- 
preffe. ) , And in like manner EFGHI, from that New- moon 
at E, to the next Full-moon at I. 
From A to E ( from Full-moon to New-moon, ) T moves 
( in its own Epicycle ) upwards from the Sun : And from E to 
I, ( from New-moon to Full moon J it moves downwards, 
toward the Sun. Again, from C to G, ( from laft quarter to 
the following firft quarter, ) it moves forwards according to 
the Annual motion 3 But from G forward to C, ( from the firft 
Quarter to the; enfuing laft Quarter, ) it moves contrary to the 
Annual motion. 
It is manifeft therefore, according to this Hypothecs, that 
from Laft quarter to Firft quarter ( from C to G, while T is 
above the Line of the Annual motion ) its Menfirual motion in 
its Epicycle adds fomewhat of Acceleration to the Annual mo- 
tion 5. and mqft of all. at E, the New-moon : And from the firft 
tp the laft quarter ( from G forward to C, while T is below the 
Line of the Annual motion, ) it abates of the Annual motion*, 
and moft of all at T, or A the Full-moon. 
So that in purfnance of Galiheo / Notion, the Menfirual add- 
Oo a ing 
