CATOPTRICO GEOMETRICL 



%$ 



cans rectam BE in E, pun&o defiderato; alte- 



rum pun&um F inuenietnr fumendo B'Fr BE. 



Nam per han-c conft uclionem obtinetnr centrutn 



circuli, cjui per G , C, A, puncta, transire debetj 



in recta DG, prout effe debet, iuxta§.$. et ob 



HG — HC— HA, trausibit circulus ex H defcriptus 



per indicata tria pun&a. 



§. 12. Ad p-raxin inuandam, fi fortaffe ali- 



cjua ex his fperanda fh , indicabo fequentem me- 



diodum , cnius ope pro quouis radio fpeculi , et 



arcu ABC inquiri potelt in diftantiam pundti E 



aut F, a medio fpecuii punclo B. Cum enim 



in G fnpponatnr effe centrum fpeculi fphaericij 



datis radio fpecuTi, et dimidio eius arcu BC, da- 



buntur in triangulo nequkuruo GHC , anguli ae- 



quaies HGC,et GCH, nec non latus CG', vn- 



de ex his inuemetur latus HG, quod fubtractum 



a radio fpeculi GB reiinquet latus.HB. In triaii- 



gulo igitur HBE dabuntur HB,HE,iatera,cum angulo 



conftante HBE =: | AD C ~ femirecto, ln hoc 



cafu; ex quibus inuenietur defiderata diftantia BB 



ant BF. Computaui hac rr.ethodo fequentem ia- 



tercuium, in quo radius fpeculi fphaerici BG po- 



nitur efTe partium ioooo. 



be 



7 1 $7- 



1 m. 



7 198" 

 7 222. 

 7248. 

 7 27$. 

 1 3 04. 



1 ABC j 



BE 



ABC 



Arcus. 





Arcus 



2.° 



7 07 2 



»8° 



i: 



7 07 c. 



2 O 



7 080. 



22 



8. 



7 088. 



24- 



1 0. 



7 Gy8. 



26. 



1 2. 



7 l 09. 



28. 



»4- 



7 12 3. 



1 3°- 



J 16. 



7 » 3 9- 



1 



Tom. V. 



M 



§. 



13. 



