C 1X 9 ] 
Proposition II. 
The mean Anomaly of a Comet or Tlanet revolving 
in a given Elliptic Orbit being given s to find 
the Anomalia Eccentri. 
The Solution of this Problem requires two diffe- 
rent Rules ; the firft and principal one lerves to make 
a Beginning for a further Approximation, and the 
other' is for the Progreffion in approximating nearer 
and nearer ad libitum. 
I. The Rule for the fir ft Affumption : Let t,f and 
p, (land as before, for the Semi-tranfverfe Axis of 
the Ellipfis, the Semi-diftance of the Foci, and the 
Terih elian Pittance ; then taking the Number n equal 
to let !Tfi:and for — — ■ ■■ - . and 
*P for— — ■ (or~rAi which conftant Num- 
— — ( or ftp \ • 
nnt—nn — i.p ' 1 t 
bers, being once computed for the given Orbit, will 
ferve to find the Angle required nearly by the. follow- 
ing Rule. 
Let Af be the Number of Degrees in the Angle of 
mean Anomaly to the given Time, reckoned from or 
to the Perihelion ; and fuppofing R> as before, to 
(land for 57,25)57, &c. Degrees s take the Number 
and let A be the Angle whofe Sine is 
71 R 
then the Multiple Angle n x A will be nearly equal 
to the Anomaha Eccentri, 
The 
