PROBLEMJTIS ASTRONOMICI. 37 



(vbi femper fLiperius ligniim valet pro Declinatione Bo- 

 reali , inierius vero pro Audrali ^nS-.ZtS-f-B-zzjgi^S 

 ^^C^, ob C:i~A:B. Igitiir ratio qiiaefita eft ipfius 

 § ad d^^Ca, atqae hinc Tangens Azimuthi , pro an- 

 giilo Temporis acmo f^^^^ — ff^,^ ob y:i— a:?. 

 Qiiodfi vero ang'ilus Ttmporis fit obtufus , vt in Fig. 2. 

 fumatur eius deinceps pofitus C G D , atque huius fit fi- 

 nus a, cofmus S, tangens y^ erit pro hoc cafu anguli , 

 qni Azimutho A K IVl deinceps pofitus eft , Tangens — 

 ig£ci- In fequentibus vero femper affumam DecHnatio- 

 nem efle Borealem, quare adhibendae funt Formulae 

 pro angulo temporis acuto tgz^A^tang. Azimuthi j pro 

 angula Temporis autem obtufo erit jgi^ — tang. anguli, 

 qiii deinceps pofitus ert Azimutho. Q. E. L 



Problema. 



III. Ex obferuatis trilnts Temporikis ZPA, 2PB, Figur» j. 

 ZPC in Fig. 3. Jl^/Iae aUmus ^ ita vt in objeruatione 

 inter vtramque media Jlella fit in ipfi vertica/i primario 

 ZB, in vtraque altera vero ab hoc aequa/iter remota , 

 imienire Altitudinem Po/i. Ad natiuram huius Problematis 

 cxcutiendam ponantur 



Temporis ZPA finus —e cofin. — / Eleu. Aequ. fin. —y 



ZPB finus— ^ cofin.nrA cofm. —\^ii-j;y) 



C P Q^finus — i cofin. zi L DecHn. tang. — u, 



Habehitur per Lemma 2. Tangcns D Z A —y^-r—^—;:^^ 



fup['ofito angulo ZPA acuto, qui nunquam ahus effe 



poteft, porro ent Tang. D Z B — ^-^^^^p^ ^ fuppofi- 



E 3 K> 



