21$ D E M O T V 



atquc omnino meretur, vt diligentins perpendatur ; 

 quam ob rem eam in fequenti Theoremate genera- 

 Ilflirro compkifti conueniet , cuius vcritas ex calcu- 

 lis , quos modo abfoluimuii (iitis elucet , dum alias 

 profunuiffimas indagationes pofiularet. 



Thcorema. 



§. 17. Si rph:icra circa ccntrum fuum fixum 



Tab. II. \'tcunque de fini fno dcturbctur, vt tcrna eius pun- 



Fi^- 5. da A, B, C in eius fupcrficie quadrantibus a fe in- 



vicem diftantia transfcrantur in punda a^ b, v; tum 



aliud pundum quodcunque Z ita transfcrctur in z 



vt fit 



I. cof.;s A — cof. 2 A coC « A-l-cof. 2 Bcof. a B-f-cof 2C cof./7C 



II. cof.^^Bzzcof.ZBcof. ^B-i-cof ZCcof Z^C-l-col.ZAcof.^A 



III. cof. ^ C = cof Z Ccof f C-i-cof. Z A cof c A H-cof.ZB coI.cB. 



§. 18. Qiioniam pundla litttris maiusculis et 

 minulculis defignata inter le permntare licet , ita vt 

 minufculac pertineant ad {\<uuni initinlem , maiulcu- 

 lae vcro ad flntum muiatum : aequationcs ctiam lc- 

 quentcs veritati erunt con(entancae 



I. cof, Z tf — cof z a co(. A rt -f- co(. z b cof kb-\- cof zcco^. A 6 



II. cof Z^— cof 5;i>co(.B^"i-cof sr cof B^ -f-co<.::£7Co( ^a 



III. col.Zt- — co(.x:ccoi'.Cf-i-cof sffcofC^i-t-cof 5rZ7C0(. C6. 



Applicatio horiim fymptomatnm ad coordi- 

 natas Orrhogonales. 



§. 19. Appliccmus nunc omncs formulas, quas 

 hadcnus inucnimus, ad tcrnas cooidiuatas, duxtftioni- 



bus 



