GENERATIONE IN CORPORIBUS RIGIDIS. 251

ricam normales, alterae fuperficiem fphaericam tangiyit, ubi prioresper centrftm mnifeiintes nulla praebent momenta, unde solas poficrioresconfiderafie fufficit, quae erunt: vis fec. VA = P fin AV; vis fec. VB= iiBV et vis fec. VC — R fiCV = R ob CV quadrantem. Haevires porro resolvantur fecundum diredlionem VF, et aliam ad eam nor-malem , ubi priores cum axe 1F in eodem plano litae nullum praebentmomentum, alterae autem vires erunt

P fi AV fi AVF - Q IiBV fi BVF _ R fi CVFquarum diretfiio cum fit ad planum 1 FV normalis, erit etiam in plano adaxem IF normali, unde cum diflantia ab axe fit = h fiFV, ob AV — F,et f BVF — /AVF erit momentum quaefitum — h ((P fi<? — Q^cofi)fin AVF /FV - R cos AVF. fin FV) at fiAVF./FV =• /FE = /$, ne-que momentum habebitur

P - Q h coQ/S — RA cof AVF . /FV

at ex sphaericis eft cof AVF./F V = /(<^ 4 * y) cofS’, itant momentuniquaefitum fit = Fhffr/S - QA co- &hj(§ + y) cof$, exquoangulus tempufculo dt genitus fit

d - §^ 2 (?/§/S- Q^oO/t? - R/(<?+»;) cofK)a M (aa cof>7 2 cofS- 2 + bbfy z cof$ 2 + cr/S 2 )

Qiiocirca minimum reddi debet haec expreffio

( ( P/^-Qcof ( ?)/^-R/(J+) 7 )cofa) a

aa cofij* cofA 2 + bbf );* co f& z + ccfB zOatuamus primo & tantum variabile, et fiet:

2 (a» cofti z cofS* + bbfy z coC$ z + cc/S z )((Vf$— Qcofj 1 ) cof$

+ R/C $ + *)/&) =

r(— aa co ty z f& cof 9- — bbfy* cof A -f ctf& cofA)

((P/d^ - Q.coW)/^-R/(^+»,) cof^)quae reducitur ad lianc formam

(P/iJ — Q cof(J) (aa cof); 2 + bbfy 1 ) cofA + R ccfQ + y)f& = »(Q^cofj 1 — ?f$) (aa cofy* + bbfy z )

.mde oritur »g 9 --RTTfio C<f + -'

Nunc fumto y variabili obtinebimus:

a(aacof))* cof3- z +M/>; 2 cof A 2 -F cc f& 1 ) (—R cof(F-b>;) cof^) =2(— aafn cof»; cofA 2 + bb fy co fy co f$ z ) ((P/^ - cofF)p-Kf (8 + y)co(&)quae reducitur ad hanc formam

RcofA (aa cofF cof^ cofA 2 — bbffify cof$ a + rfcof(<J'+^)/ 1 & 2 ) =(OcoW- ?fS) {bb-aa)fy cof»,/ScolI 2r Ii 3

ubi