Erect, and is so brought into the Eye by the Eye Glaß; tbe Eye Glaffes themVftlves in neither Cafe having any thing to do with the Erecting or Inverting,but meerly in reprefenting in the sirae posture the Species imrnediately beforethem. So that one Convex Glaß as pofited in a Telefcope Inverts ; the se-rand (that is the first Eye Glaß) does nothing totvards the Erecting or Rever-sing, but reprefents the Image as it is in the Distinet Bafe of the Object Glaßbefore it, that is Inverted; the third Glaß Erects, or rathet Reßores whatwas before Inverted ; the-.fourth reprelents the Image as it reeeives it from--tbe Distinet Bafe of the third, that is, Erect.
XIII. i. Mr .Au^out has found that the Apertares, v/hich Opticlc Glasses The A;.,.«’an bear with Distinctneß, are in about a (iibdupiicate Proportion to their °sLcngths : and accordingly he' hath made the following Table. hM. uzc
by M. Auzout*N. 4.« P. W
Lengtbs
Apertares so
r
Lengtbs
fit-'
Apertur es for
of
°J
Gksis.
Excellent.
GooL
Ordinary.
Glaser.
Excellent.
Gooi.
Ordimry.
stet. In.
In. Lin.
In. Lin.
In. Lin.
Leet. In.
In. Lin.
In. Lin.
In. Lin.
4
4
4
3
3 4
2 10
2 4
6
5
5
4
3 °
3 8
3 2,
2 7
9
7
6
5
35
4 0
3 4
2 IO
I 0
8
7
6
40
4 3
3 7
'2 1
i 6
9
8
7
45
4 6
3 10
3 2
1 0
1 1.
IO
8
50
4 9
4 c
3 4 -
i 6
I o
1 1
9
55
:■ 5 0
4 3
3 6
3 o
i i
I c
IO
. 60
5 2,
4 6
3 8
3 6
i z
I I
1 1
65
5 4
4 8
3 10
4 o
1 4
i a
I o
70
5 7
4 10
4 0
4 6
1 5
1 3
■ I I
75
5 9
5 0
4 2
5 o
i 6
i 4
I I
80
5 u
5 2
4 5
5
1 7
1 5
I z
90
; 6 4
5 6
4 7
7
i 9
i 6
I 3
100
6 8
5 9
4 JO
8
I IO
i 8
: 4
110
7 5
6 5
5 3
9
X XI
i 9
i 5
.15-0
8 0
7 0
5 11
10
; % i
I IO
i 6
ZOO
9 6
8 0
6 9
u
, 1 4
z o
t 8
'270
10 6
9 2
7 8
H
r'z 6
z z
i 9
ZOO
ii 6
io- 0
8 5
1 6
z 8
■ z 4
i 1 1
350
12' 6
10 9.
9 °
18
Z IO
z 6
x *
400
13 4
11 6
9 8
to
3 o
2 7
' z z
2.. This