ii SCIENCE—ADVERTISEMENTS 
Leitz’ Binocular Microscope 
“GREENOUGH’S MODEL” 
with image erecting prisms. 
Since new optical data are involved in our four sets of paired 
objectives, this Microscope offers Special Advantages, as 
regards a very distinct image to the rim. 
Another feature of the Leitz Binocular Microscope is the 
characteristic mounting of its prisms—mounted in steel springs 
(not cork). This is the same device as employed in our Prism 
Field Glasses. Such a mounting guarantees the permanent 
adjustment of the prisms. 
This Microscope is also made in Detachable Model, with 
hardrubber fork, as well asin Folding Form, compact in travel- 
ing case for field work. 
Special DUTY FREE PRICES to Educational Institutions. 
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New York 
30 East 18th Street 
United States 
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