E*ROM impressions come conceptions. 



From conceptions arise creations. 



From creations progress advances. 



Youth is impressionable imaginative 



and susceptible to development when 

 correct impressions of things as they 

 exist, but otherwise unknown to it, are 

 shown through the powerful lenses of 



BAUSCH & LOMB 



Microscopes 



The Accepted Standard 

 There is a Bausch & Lomb model for every 

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BAUSCH & LOMB OPTICAL CO. 

 408 St. Paul Street Rochester, N. Y. 



New York Washington Chicago San Francisco 



Leading American Makers of Photographic Lenses, Micro- 

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that eyes may set ' 

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W. Watson & Sons, Ltd. 



(British Made) 



STUDENTS MICROSCOPES 



The "Praxis" Stand is the Student's model par 

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A few special points 

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 adjustment. Con- 

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 Catalogue of Microscopes and accessories for 

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W. WATSON & SONS, Ltd. 



Established 1837 

 313, High Holborn, London, England 



Naturalists 9 Supplies 



We carry stock for prompt delivery 



I. Collecting Utensils. 



II. Breeding Apparatus and Cages for Living Animals. 



III. Preparing and Preserving Utensils. 



IV. Cabinets, Insect Cases and Lining Material. 

 V. Magnifiers, Microscopes and Accessories. 



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VIII. Miscellaneous Naturalists' Supplies. 



IX. Oologists' Supplies. 



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K-S Museum Cabinets of Glass and Metal 



New Illustrated Biological Catalog will be sent free of charge upon application 



THE KNY-SCHEERER CORPORATION 



Department uf Natural Science 404-410 WEST 27TH STREET, 



G. Lagai, Ph.D. NEW YORK CITY, N. Y. 



