34 DE SOL. QVOR. SVPERF. IN PLAN. etc. 



54. In numeris crgo dcterminatis confidere- 

 mus hunc ca(um : 



y z= 2 <p -\~ :i (p^ X et z — (p'-^2<p\v 

 ▼nJe fad.i ciiminationc litterae (p fequcns clicitur 

 aequatio : 



^y'x-{-^2y\vxz-jy - i Sjx z -f 2^xxzz-\- 2Z — o 



quae crgo eft pro (olido , cuius fuperficicm in pk- 

 num explicure licct. 



ME- 



