= (.3) = 



qiio fllum fiipcr plano horizontali iuxta lincam redam vnifor- 

 mitcr protrahitur , cuohiamus. 



Dc vera curna tradtoria, dum filum per lincam 

 rcftam vniformiter protrahitur. 



§. 4.0. Protrahatur igitur fihim per hncam redamTab. L 

 AU cclcritate — f, et elapfo tcmporc —t pcrdudum fit f 'g- <J' 

 vsque in T, dum motus inccperit in pundo A, eritque fpa- 

 tium AT~fr, corpufcuhim autem nunc fit in Y, ita vt fili . 

 longitudo fit T Y — a. Vocemus autem anguhim A T Y =: ^, 

 vnde demiffo ex Y pcrpendiculo Y X erit T X=ia cof et 

 YX — aHnJ, ita vt pofitis cocrdinatis AX — .v et XY —jy 

 fit 



x=zCt — ^cof. ^i dx — cdt-had^fin.O, 



j~a(in.$ i dy =z a d^ coC. &. 



Ponamus autem porro ^> = tang. (p, ita vt Cj) dcnotet angu- 

 him, fub quo elementnm curuae defcript.ie Yj ad axem AB 

 inchnatur, ita vt lit tang. (f) = — iii££^l-— . 



§. 41. Dcnotct niinc M maffam feu pondns corpus- 

 culi, ct ponatur tenfio fili T Y — T, quac ergo eft vis, qua 

 corpufculum a filo protrahitur, quac fccnndum diredioncs co- 

 ordinatarum rcfoluta praebct vim fccundum AX~Tcof ^, 

 ct vim fccundum X Y — T fin. ^, vbi notandum efl hanc vim 

 T adhuc cffc incognitam. Practcrca vcro ctiam corpufcuhim .1 

 fridionc follicitatur, cuius vis fit = F, quae cum fcmpcr di- 

 rcdioni motus fit contraria, eius direiftio erit/Y, quac crgo 

 refoluta pracbct vim fccundum A X =1: — F cof (J) ct vim 

 fccundum XY — — F fm. 0. His igitur viribus colligcndis 

 fumto elemcnto temporis dt conltantc piincipia motus fcqucn- 

 tcs fuppcditant acquatioucs: j^ 



