CHAS. LENTZ & SONS 
Cinear masnifping powers of ObjectiDes 
and €pepiea$ 
IMAGE DISTANCE 250.0 MM —TUBE LENGTH J60.00 MM. 
Objectivks. 
EYEPIECES. 
2 In. 
iln. 
I In. 
1 In. 
i In. 
50 mm. 
40 mm. 
25 mm. 
l8mm. 
12 mm. 
Inch. 
mm. 
3 
75-0 
II 
16 
21 
28 
35 
2 
50.0 
16 
22 
30 
40 
54 
li 
37-0 
23 
33 
44 
56 
70 
I 
25.0 
30 
41 
53 
69 
85 
2 
s 
17.0 
55 
74 
96 
130 
165 
1 
12.5 
88 
120 
155 
200 
265 
1 
63 
190 
260 
355 
455 
560 
* 
5-0 
230 
315 
410 
550 
710 
1 
4.2 
265 
340 
450 
585 
750 
1 
3-2 
345 
460 
590 
770 
980 
1 
2.1 
580. 
810 
1060 
1400 
1760 
1 
1.6 
820 
IIOO 
1420 
i860 
2350 
Above magnifications can be considerably increased by lengthening the draw 
tube or by inserting an achromatic amplifier in the society screw provided in draw 
tube. 
28 
