( 6^1 ) 
h'ircHll ferlfherid mdmt pmBa Reflcxiom qu<&jttl. Hiicufque Dn.HagS 
Quae Dn.Shfm ad hsec repofult trinis epiftolis,fic fe habent ^ 
U ^^ ad Alhazcni frohhm^ mditamfm haUenpts, rudia lick & mpa- 
Ika^tui juris (unt *. De w igimr difpone prom luhet. Sim- 
plkifmaefl^ & maximiingeniofiiNdUiffimi Hugenii con- ^Tetiemfcfa' 
ftruUio. Vidit t^uippeVir MPitiJJimtis^ qua ratiom ad omnes ^^^^^^^^ Editor, 
caffisexieridipojfaHyptrhohaqualif^m/aterum, qmm in ^^r^iuJs^^'^"^ 
cafu mguU n^ijefe fiatim offerre pratcedenti^ni meis infinu- 
averam. ^ Pojfet quoque ex infimis Ellipfibus,^//^ adhiberi pojfmt, mafeUgl 
mn dlfficilis confiruEiionis : fed piget tamdiu in eodem Problem ate bar ere. Su- 
ferejl tamen aliquid^ quod contemplationem hfibet non injmmdam nim. cum 
JeBiones, qu£ cHrn circulo dato ad Problernatis folutionem adhibentur^ ilium in 
quatmr pun^is [tcmt^qmnm duo t ant urn reflexionifervimt^qHaripoffet^quod' 
nam Problema [oh ant dm reliqua, & qmnam verbor am forma concipienda fit 
Propofitio.Ht quatmr illos cafm compleUatur. Deinde, annon etiam iidem qm* 
tmr cafm occurrant cum punEia data ^qualiter diflant a centra ? Fale. Daham 
Leodii F/// Junii CIOIoCLXXII. 
2. C7/^r.Hu genius nm alia utitur analyfi quam mea^ qH<z Parabolam mo 
tantnm cafu admit tit* S^od m evident ibm tibi confiet^ Aquation em quam con^ 
Uruxit hic adfcribam, Repete memoria^ fi placet ^quA fecundis cpiris adte fcrif^ 
(i^d^ invemes,me duos cequationesy problemati per HyperbsUm circa afymptotvs 
folvendo idoneas^ affignajfcy has nimirtim \ 
2zbaa - 2znae - qqba + qqne = bzqq - z q q e, 
Et bzqq - 2znae - qqbaf qqne = 2zbee - zqqe • 
AC fubjecilfejevi mutatione (fubfiitUendo, ex.gr, pro qq, ejm vaUrem^t + ee) 
inveniri pojfe inflnipas Hyperbola & Ellipfes, quz cum circuh dato Problem % 
folvereatt Nunc in prior e ex his aquationibm pro bzqq ponntur ejm valor, fie t 
zbaa - aznae « qqba + qqne = bzce ' zqqe, 
Sive aa - ee . m t - '^f^ . 
Jtque hdcefi <£quatiOf quammagnoingenn acumine ^ ac pari facilitate con- 
firuxit vir dQEiiffimUs, ^od ut tibl pluribM^ probem.opm non eft^ quando la» 
bore non multo rer/i- ad calculos revocando id agnofcere poteris. V ale, Dab, Leo- 
diiZjuniiCIOloCLXXll. 
3. Problematis alhazeniani memoriam dudnm objecernm.Vir Clh fed Uteris 
tuis admonitm temperare mihi non potui^qnin faciliorem e'jufdem conflruEiionem 
qn<trerem. Incidi autem nuperinfequemem.qf^^breviermcum dari pojfe vix 
credam.committere nold, quin earn judicio ac cenfur^ tuji fubmhterem, Sint 
igitur punEladata E 5*, dr cuius cu]m centrum A ^ ]unUvis 
EA,BA,fecantihm circulum in F& CS fiant tres proportion •»'V.Fr^., III. 
nales E A,F A ,F A , & tres iterum B A,CA,XA: tumjun^ 
^aVX.ac prodr4^dutcunque,(verttce X, latere tranfverfo VX, a': reBo ipfp 
<zqudli)defcribatur Hyperbola XP, c^rj^s applicat^ ad diametrum VXG, pa- 
ralleU fintreH<z AB: illaenim fatisfAcit propopto in cafu fpeculi convexi, ut 
ejus oppofita in caCn concavi. Si afymptotos dsfideres, facile reperiri pofint, 
Uuu UUU i pro- 
