BAIRD &TATLOCK. (LONDON) LTD. 



1303-1310 



Triple Aplanats (Bausch & Lornb's) . Composed of two meniscus lenses of flint glass, 

 separated by a double convex lens of crown glass. Field is large and has a perfect 

 correction for chromatic aberration, as well as for flatness, astigmatism and distortion. 

 These magnifiers are of new construction, and we recommend them for the highest class 

 of work. Their working distance is a little short of a simple lens of the same focus. 

 Furnished in two styles of metal mounting, engraved " Triple Aplanat " with the focus. 







E. F= equivalent focal length 



1311-1317 



Hastings Aplanatic Triplet Magnifiers (Bausch & Lomb's). After formulae by Prof. 

 Charles S. Hastings, Sheffield Scientific School, Yale University. These magnifiers 

 are among the most perfect produced. Their excellent corrections have always been 

 appreciated by scientists. The angle of view embraced is very large and the working 

 distance almost equal to that of a simple lens of the same focus. Furnished in two styles 

 of metal mounting, engraved " Hastings Triplet " with the focus. 



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