USE OF Till-: ii.wn magnifier 



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Fig. 5. — Diagrammatic sectional view of spectacle magnifiers. Each con- 

 sists of an objective of two lenses, and an eyepiece of two components. The 

 diameter of the field of view on the object is about five centimeters. The defini- 

 tion is good to the edge of the field, and the stereoscopic effect is excellent. The 

 figure shows a magnifier for normal vision, adjusted to the particular inter- 

 pupillary distance of the wearer. Spectacle wearers may have caps fitted over 

 the eyepieces, with their correcting distance glasses, including corrections for 

 astigmatism. The writer found that the magnifiers as figured may be used with 

 advantage for dissecting. The two miniature telescopes can be fixed in 

 circular openings cut in the centers of convex distance spectacles. An adjustable 

 frame can be obtained, in which the distance of the lenses can be varicfl to suit 

 the interpupillary distances of different observers. 



