[ *vt ] 
Bat in thefe Orbits the Rules in the firft Corollary 
to the fecond Propofition moft frequently take Place-, 
efpecially the laft ; and the Calculation may alfo be 
further abreviated, by putting the fquare Root of io, 
or the Integer 3, for the Number n. 
Example. Suppofe the .mean Anomaly to be 
o®, 0065-22, or 23", 4792: Here, fince M is 50 times 
lefs than the limiting Angle, the Rule in the firft Cafe of 
the firft Corollary may be ufed ; that.is, to take theSinc 
of the Angle A = ‘-dUll. 
Wherefore, if the Number 3 be put for n, the Sine 
of A, which is ~, will be =0,00116367; and con- 
fequently the Angle A will be 4'. 00", on j and the 
multiple Angle n't A to be aftiimed for the Anomalia 
Eccentri will be 12'. 00", 033, the Error of which 
will be found to be about -f of a Second. 
Example IV. 
For the Orbit of the great Comet of the Tear 1680. 
This. Comet, according to Dr. Halley, performs 
its Period in 575 Years; and was in its ‘Perihelion 
on the 7th of ‘December 1680, at 23k. 09' /Eq. T. 
at London ; th tperihelian Diftance p is 0,000089301, 
in.Parts of the mean Diftance t : Wherefore fuppofing 
the Number n to be VTi, the conftant Numbers for 
the Orbit will be T=o, 2000161 ; ?*=o, 000017862, 
and the limiting Angle =^k-/T will be about 4 of 
3 * 
a Second. 
Example. Suppofe the mean Anomaly to be 
3', 3i",4478 or o°, 05873541, (as it was at the Time 
of the firft Obfervation made on it in Saxony, on 
November 
