296 Opuscula * 
Porro fi fit ds elementum peripherlse , & radlus ad peri- 
pheriam fe habeat ut i : A , erit fx^ ds-=- . Eft autem 
generatim J?c ds:=z—~ .b /> ds-^.b(^b -x^j^. 
X , 01 polito ^-A-nOjelry^ ds zz. 'b Jx cis, 
Fiet igitur fpcUszn-l b'^ fx' ds — ^^b'^ fx^ ds = ^^b^ ec. 
& fi fumma omnium a'* , ^**, a-*^ » dividatur per circula- 
rem peripheriam ^A prodibit medius poteftatum earumdem 
valor \b^ ^ i b'* , "i '^^ > 7^ > fciiicet valore per totam 
peripheriam uniformiter continuato jequalis fumma conficere- 
tur . Quod fi denique valores ifti in duabus antecedentibus 
feriebus fuo loco fmguli fubftituantur , prodibit nodorum mo- 
tus , qui tota Pianetse attrarti revolutione medius cenferi pof 
fet , ubi Planeta attrahens datum orbitje fua; locum , datum- 
que afpcflum cum nodis ipfis immutabiliter tueretur. 
Itaque fi Planeta quifpiam inferior a fuperiore perturbe- 
tur , medius motus nodorum utriufque orbirx , qui dato fupe- 
rioris Planetae ioco integra inferioris Planetae revoiutione re- 
Ipondebit, aequalis erit — ducto m 1- — — — 
^ ^ M 2ai j^a> i6a^ 
16 a'' ^ia^ iiZcP 31^' i28a' 256^1' 
. ^ ( — - — — ^ _j — 
~- C^""^ — 2 ~ — r3- Dato panter mfe 
rioris Phnetae loco , motus medius nodorum Planeta: fu-^^^io- 
nons jenualis erit ■ — duCto in — — — -f- — - — -H 
Sii'* Ji8i*^ 32/-^ iiS^3 2561»^ 
- — — — . I j ? -*f^ . ■ I ^ « 1 
2048/»^ 2NU^ 6^i,-» 1024/;^ 
Ut habeatur motus vere medius nodoruin pro afpec^u 
quoiibet Planeta: attradi , attrahentifque , medium medioruin 
omnium motuum accipere oportebic , & Kewtoniano more 
pro 
