[ 7.1 ] 
and the like ratio, in the arc PA, by .9852467 
M). 
3. Multiplying therefore the forces k and — K, 
found in § 6, by g and by h, fubftituting the products 
for c , in the formula, with the arcs CN, and NG, 
refpedively, and finifhing the operation as for the 
circle, the regrefs, in a periodical month, will be 
yf48".3, and the progrefs 16489' . 8 : whofe dif- 
ference is the driest mean motion fought, 3 0 ai" 
1 - 
* 2 • 
13. But nearly the fame conclufion may be ob- 
tained, and with much lefs trouble, as follows : 
In the circle CGD-, take CM— 35 0 15' 52", and 
thro’ P, the point where MK perpendicular to TC , 
cuts the orbit, draw TPN meeting the circle in N. 
Then, if R is the regrefs of the apfis in a circular 
orbit, R ke the regrefs in the oval CPA. 
In like manner, having infcribed in the orbit, the 
circle Amh, and made a fimilar conftrudion for the 
reft of the quadrant P x 
Am 
~Ah 
I 
2 > 
will be the dired: mo 
tion in the oval, P being the dired: motion in a 
circle. 
Thus, the angle of variation MTN being (in Dr. 
Halley’s tables) 33' 9", the fubduplicate ratio of CM 
to CN will be 1.007927, and that of Am to Ah, or 
of GM to GN, will be .99499. And therefore R (in 
§ 9) will be augmented to 1386''. 6, and P diminifh’d 
to 41 23' 1 : whofe difference, multiplied by 4, gives 
3 0 2' 25''! j exceeding the former only by about 4". 
14. The 
