8 
3 
4 
5 
2 
12 
2 
*5 
7 
6 
3 
U 
15 
o 
6 
o 
o 
o 
o 
o 
6 
6 
Mathematical InflrunttnU . 9 
And fo in proportion for any other length. 
All other forts of refracting teilefcopes at the 
ufual prices. 
56 Wilfon’s pocket microfcope. 2 
57 Ditto. -- — 2 
58 Ellis’s aquatic microfcope. 2 
59 Ellis’s and Wilfon’s microfcope in one 
cafe. — — 4 
60 A tingle and double aquatic microf¬ 
cope. — — 7 
61 The double conftruCted microfcope. 6 
62 Ditto with a triangular foot in a flat 
mahogany cafe. *— 
63 Culpepper’s double microfcope. 
64 A tolar microfcope. -— 
65 A ditto. — — 
66 The new variable microfcope. 
67 A folar microfcope, to be applied to a 
new invented camera obfcura, that 
may be ufed either in the fun-fhine, 
or with a lamp contrived for that pur- 
pole in winter evenings. 
68 A pocket camera obfcura. 
69 A ditto. •— 
70 A ditto larger. 
71 A pyramidical camera obfcura in wain- 
fcot. — 
72 Ditto in mahogany. 
73 An inftrument for taking pcrfpedfcive 
views. — 
74 Concave and convex mirrors, from 
75 Prifms, from y 
76 Zografcopes for viewing prints, from 
77 Opera glafles. 
78 Ditto. 
0 
Ic k 
6 
—■ 1 
1 
0 
I 
5 
0 
•a in wain- 
3 
3 
a 
4 
14 
6 
lerfpedtive 
—- 6 
6 
0 
ors, from 
6d. to 26. 
a 
0 
s. 6d. to 2 
2 
0 
18s. to 3 
3 
0 
0 
8 
0 
- 0 
'■ 5 . 
0 
7 ^ 
Di 
; CIO 
