Microscopy. 
b /, a myopic condition of — 8 D. may be produced if 
k convex glass of + 6 D's is placed in front of the one at f. 
in order to produce a myopic condition of — 8 D's. When this con- 
dition is produced, we may obtain higher magnifying powers, as 
follows: 
Diopter.and object on the left, drawing and silver mirror on the right, 
^'&L?^ 
'^" 
Slr""^" 
Magnifica- 
'S^Fr-- 
Distance of the 
drawinfr paper 
+7 
+8.5 =7.5+1 
+ 11 = 6+5 
+13.5 =7.5 + 6 
d 
so'"''' 
44 
7 
9 
10 
-9 
-9 
-9 
400 mm. 
400 " 
400 " 
These combinations produce perfect images, except when the 
strongest magnifying power is used, when a slight distortion is 
visible on the edge of the field of vision. 
The above described camera, together with a case of 25 glasses, 
may be obtained of R. Jung, Mechanic and Optician, in Heidel- 
berg, for 120 marks. 
