nNDVLi cnvsQyE comfositi. 9 



iny inuenietiir pro tota femiordinata BD , fumma 

 omnium CE~.Eez:z(m}n^2mx~\-xx-\-jjy\y\ent er- 

 go nunc/P. CV^—f(mm -+- imx -\-xx-\-^yy)ydx , et 

 JA.MC^fivt-^-x^ydx j adeoque 



/— ^^j^—:--^ . . fi axis ofciilationis efl: 



—S[mm-imx-^xx-^yy)ydx _ 



OO.Et/=i j(.^^)^d;c ) ^i axis ofcilla- 



tionis efl: 2O2O. 



16. Confideremus porro fuperficies fo- 

 lidorum rotundorum ex reuolutione figurac 

 cuiuscunque BAD circa axem CD ortas. Hoc 

 cafu pondufcula P , fiunt zonulae conicae , 

 quae nafcuntur ex elemento B^ curuae circa 

 axem CD in gyrum ado , vocando vero periphe- 

 riamcirculi^ , cuius radius efl: i , eiusmodi zonula 

 fiet —pyds, eius diftantiaab axeofcillationis — l/(?w;« 

 ■4-2»z.rH-.r.r-Hj)'j')adeoA't fit fV.C'P"=if{mm-\-zmx 

 xx-{-yy)pyds. Item M.C Nl=f(m-{-x)ypds,Qv^o 



2 



]( — /P-CP > — Jjmm-i- ; mx-^-xx-^yy )yds -^ p 1 



^ M.CM. '^ J(m-i-x)^ ' 



j_^Jimm-^mx.^xx.^yy)yds ^^ ^^-g ofciHationiS fit in 



* — Jim—-x)yds ' 



altera parte 2O2O. 



17. Qiiantum ad haec folida rotunda ipfa , fi 

 corum centrum ofcillationis inueniendum fit , cu- 

 iiis quaelibet fcdio axi normalis efl: circuhis BHI 

 cuius radius BDni)'. Sit in femicirculo HBI zonu- 

 la FEG^^ cuius radius DE=:?*t , primum inueniri 

 dcbet fumma omnium CE^.FEG^^, quae continen- 

 tur in toto femicirculo HBI •, efl: vero femicircuhis 

 ¥EG zz^puii) fi p iterum defignet circumferentiam 

 Tom. III. B cuiu^ 



