{ i?i5 ) 
to be only an approximation to the true one^ xvherein they 
defcribe Area's at the other j^^:»/' that are proportional to 
the timesjand as fuch it is exprefly mentioned by Kepler in 
his Epitome Ajhommis Copernicanie 5 bot if the diftaoce be- 
tween the^d be great, this method will not give the exai2: 
place of the Planet, and therefore it wants the approxima- 
tion of BuUUldus^ which is only a bearer approach to truth 
Here alfo he confiders the Oval Figure, in which Monfieur» 
C/^/J/Wfuppofes the Planets to move 5 and he proves, that if 
a Planet moved in that Curve according to Cajjinh 
Theory, it would defcribe round the Sun equal Areas 
in equal times 5 and by coilfequence a Centripetal force 
of a determined kind afting upon the Planet, might finake 
it defcribe this Curves whereas Dr Ward% Theory is 
Phyfically impoffible, there being no Centripetal force 
towards the Sun, that can make them move in an E!- 
lipfe according to this Law 3 but then he telk us, that 
the Theory ot Cajfini do6s not anfwer obfervations, nor 
will give the true Anomaly of the Planet, and it?? diftaoce 
from the Sun. After this he comes particularly to ftiew the 
methods of determining the Orbits of the Earth and Planet^ 
their Excentricities^ pofition of their Apfides and Nodes^ 
and defcribes all the Tables lhat are neceffary to calcu* 
late their motions, together, with the manner of making 
them s and he alfo fliewsthe way of finding out the Mag- 
nitudes, DeoGties and Figoresof the Son andPlanets^ and 
the diftances of the fixt Stars^ where he takes notice, that 
the annual different- diftances of a fixt Star from the Pole 
(which Mr Flamfieed in his Letter to Dr Wallk.. Printed ia 
the third Tome of the Drs Works, f :-;(€rved in 
the Polar Star) doesnoi: oecefiarily iwm i;- ..uUuCK ParallaK ^ 
bot may proceed from other caufes^ fo that iwm this obferva« 
tion, we cannot coisclndethe paralfa^c of the fixed S'^ars, nor 
- does|it direftly provethe motion of theEarth/.v r/ :Flam* 
fteed x\mk he has done by itAiid iris the cnoreliK.cA^^diat thi^ 
'variation of the Stars diftance from the Pole^ ot iefved by 
Mr Flamjieedt proceeds from fotne notation^ fince the young 
