AERIS IN TVBIS. 375 



vnde deducimiis : 



I. 2 X dx dS> — ddx -h2.dydS 



II. \ d d X - X d dy -^,- ^j dy dS - 1 X d zdS zz O 



III. ddz-zzdxd^i — o 



IV. zddy-jddz-\-zzdzdS — o 

 hincque integnindo 



I. xxdS—dx-\-iydS-\-Con^.dS 



II + 111. ydx-xdy-\-dz-\-jydS>-^xzdS> — Co\\^.d^ 



IV. zdy-ydz-^-zzdSzzQon^i.dS. 



Omnes has tres conftantes nihilo fumamus aequnles , 

 et vltima praebet^= — S, ita \t lit j— — sS, 

 vbi cnnflantis additione non eft opns , quia loco S 

 fcriptum conciperc licet S -|- - vti fupra. Pofito 

 igitur y — — zS ex prima fit d x z: d S{xx-\- 2. z S), 

 et ex fecunda 



-Ss^.v + SAY/^-.rs^S + ^;::;4-SS;s^^S=:o 

 quae pcr z z diuifa et integrata edit 



-^^-i + ^S'-i-^A = o ideoque xjni^^^J 

 hocque valore in nrima fubfiituto fit 

 dxzzdS{x.v'-\-^^^pi) 



cui cum fatisfaciat a' — — | , ponatur xz=:— l-hi 

 critque o :=z d v -- ^^ -h '-^'^ -\-dS, cuius in- 

 tegrale , 



BSS-i-AAS-AS*-^S' 

 V (TT^ ruppeditat 



