March, 1907.] 



KNOWLEDGE & SCIENTIFIC NEWS. 



vi 1. 



THE BAUSCH & LOMB 



world-famed 



MICROSCOPES & ACCESSORIES 



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■B 



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g Photographic Lenses, jj{ 



A SIMPLE TREATISE. j*j 



By CONRAD BECK and HERBERT ANDREWS. Ttl 



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9 



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This book contains 323 pages. It is written in a 

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Section 

 Section 



COMPLETE ILLUSTRATED MICROSCOPICAL CATALOGUE 



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U'i 



B 



1 



H 



Section III. 

 Section IV. 

 Section V. 

 Section VI. 



Section VII 

 Appendix I 

 Appendix I 



CONTENTS. 



-FUNCTION OFTHE PHOTOGRAPHIC LENS. 



-GLASS AND THE MANUFACTURE OF 

 LENSES. 



-CORRECTIONS. 



-PROPERTIES OF LENSES. 



-TYPES OF PHOTOGRAPHIC LENSES. 



-PRACTICAL APPLICATION FOR DIFFER- 

 ENT CLASSES OF WORK. 



—LENSES FOR SPECIAL PURPOSES. 



-EQUIVALENT PLANES. 



.—LENS TESTING. 



CATALOGUE OF APPAHATVS. 





R. & J. BECK, Ltd., 68, GORNHILL, LONDON. 

 Practical Notes on Telephotography. 



FREE ON APPLICATION TO 



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6R> 



KNOWLEDGE 



And ILLUSTRATED SCIENTIFIC NEWS 



VOLUME FOR 1906. 



OVER 300 PAGES AND 200 ILLUSTRATIONS, 

 many being Full Page Plates. 



Bound in Blue Cloth, Gilt Design and Lettering, 8s. 6d. net. 

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