Barrow, Isaac - Lectiones opticae & geometricae : in quibus phaenomenon opticorum genuinae rationes investigantur, ac exponuntur: et generalia curvarum linearum symptomata declarantur

Scan	Original
81	63
82	64
83	65
84	66
85	67
86	68
87	69
88	70
89	71
90	72
91	73
92	74
93	75
94	76
95	77
96	78
97	79
98	80
99	81
100	82
101	83
102	84
103	85
104	86
105	87
106	88
107	89
108	90
109	91
110	92

9375

I. _CAtoptricâ circulari defunctus ad Dioptricam promovemur;_
quorſum incidentium quotcunque refractis unâ ſimulo perâ
delineandis, adeóque reſractionum ſymptomatis organicè pertentan-
dis modum imprimìs exponemus, præ cæteris, opinor expeditum.
Seorſim ad v γ æqualem diametro (NG) circuli refringentis deſcri-
batur circulus v π γ. item habeat v γ ad S γ rationem illam, quæ re-
fractiones determinat (illam autem deinceps, ut antehac, conſtanter
nuncupabo rationem I ad R) & ſuper diametro S γ deſcribatur quo-
que circulus SH γ. Incidat jam radius quilibet MN P, cui con-
11Fig. 107.
108. veniens deſignandus eſt refractus. ut hoc aſlequamur, circulo adpoſi-
to à V adaptetur v π = NP; & centro γ per π deſcriptus circulus
ſecet circulum SH γ in H; connexáque γ Hcirculum v π γ interſecet
in ξ. demùm connexâ v ξ, circulo NPGaccommodetur NX =
v ξ; erit NX ipſius NP refractus. Etenim (ductis GP, GX) eſt
γ H. γ ξ : : (γ S γ v : :) I. R. hoc eſt γ π. γ ξ: :I. R. hoc eſt
GP. GX: : I. R. cùm itaque ſint ipſæ GP, GX recti ſinus angulo-
rum GN π, GNX(quorum GNPeſt angulus incidentiæ) liquet
propoſitum.

II. Ad ipſa _Symptomata_ progrediamur exponenda radiis ad circu-
lum refractis competentia; quorum illa pro more primò pertractabi-
22Fig. 109. mus, quæ radianti puncto conveniunt ad infinitam quaſi diſtantiam
poſito, ſeu parallelos ad ſenſum radios ejaculanti. Quocirca per
circuli refringentis Centrum C punctúmque de longinquo radians
protendatur recta AC Z; tum fiat BZ. CZ: : I. R; nec non di-
vidatur CZ in F, ut ſit FZ. FC: : I. R; & centro F per Z deſcri-
batur circulus EG Z. his peractis, accipiatur jam quilibet ad AC
parallelus MNP(convexis incidens an concavis partibus perinde
fuerit) dico ſi recta NC (ab incidentiæ nempe puncto per refrin-
gentis centrum ducta) circulo EGZprotracta occurrat in G; &

Page concordance

Text layer

Text normalization

Search

Scan	Original
81	63
82	64
83	65
84	66
85	67
86	68
87	69
88	70
89	71
90	72
91	73
92	74
93	75
94	76
95	77
96	78
97	79
98	80
99	81
100	82
101	83
102	84
103	85
104	86
105	87
106	88
107	89
108	90
109	91
110	92

Scan	Original
81	63
82	64
83	65
84	66
85	67
86	68
87	69
88	70
89	71
90	72
91	73
92	74
93	75
94	76
95	77
96	78
97	79
98	80
99	81
100	82
101	83
102	84
103	85
104	86
105	87
106	88
107	89
108	90
109	91
110	92

Scan	Original
81	63
82	64
83	65
84	66
85	67
86	68
87	69
88	70
89	71
90	72
91	73
92	74
93	75
94	76
95	77
96	78
97	79
98	80
99	81
100	82
101	83
102	84
103	85
104	86
105	87
106	88
107	89
108	90
109	91
110	92