jii METHODFS NOVA ET FJCILIS 



§. 30. Ad runimam Ycio ipdirum M.CQ_ innenier)- 

 dain , multiplicecur clemcntum M M ?« ;/; — 2 dx V ( 2^?,?; 



— XX ) per C P zn <z - .V , } rodibit 2 ( <? - .v ) dx V ( 2 a-o; 



— .vji"), cuius integnilc c(l |^ 2 tf.v - .v.v)' in quo fi po- 

 natur AP— AH, hiibebitur/M. CQ_ pro toto legmen- 

 to BAD~|BH^ Longitudo crgo pcnduli fimpli- 

 cis ilbchroni crit ^-^-^z — 3^ — jAH. Si fi-.it legmc- 

 ntum hoc aequale lemicirculo, fient BHzr<7, AH 

 ~tf , pofitaquc ratione mtcr diametrum ct periphcriam 



I : TT crit arca femicircuh zr^,--. Pro femicirculo crge^ 

 •vacillantc erit longitudo penduli fimphcis ifochroni n | 

 'na—^a^ leu quam proxime lla. Semicirculus crgo 

 radii 20(5i fcrup. ped. Rhcnani ringuUs minutis iecundis 

 vacihationcs abfoluet. 



§. 31. Si tantum arcus circuHBAD materia vni- 

 formi conllct , reperietur / M . A M" = 2 a'' ( BAD - BD) ; 

 atquc /M.CQ^zr^-.BD. Ergo longitudo penduH fim- 

 phcis ifochroni erit 'ziz — jp — 2 ^. Aequetur arcus to- 

 ti femipcriphcriac erit longitudo pcnduh ifochroni ~ a 

 {1: — i) — \a qiiam proxime. Minore ergo tempore 

 femipcripheria quam fcmicirculus vaciUationcs abfoUiit. 

 Ceterum in genere notari debet de his motibus reciprocis, 

 ccntrum grauitatis fempcr infra ccutrum bafis C fitum 

 effc deberc: nam fi in ipfo ccntro C ccntrum grauita- 

 tis exiltat, corpus cx fl:atu quictis dctiirb.itum non re- 

 ftitnetur, fed quiefcct. At fi fupra C ccntrum grauitatis 

 exifiat corpus non fbUim non motii rcciproco feretur, 

 fed pcnitub fubucrtctur. 



§• 32. 



