SCIENCE 



Friday, June 1, 1900. 



Single Copies, 15 cts. 

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Our stock of Australian and Japanese 

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flabelllformls, Phyllospongia follasceilS, Ph. Tflnm, &c.; and the exquisite glass-sponges of Japan (Hy- 

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A NEW CATALOGUE 



To readers of Science I shall be glad to mail free the 1 24 pp. 

 Catalogue (issued June 1st), "Electrical Measuring Instru- 

 ments and other Scientific Apparatus" — manufactured chiefly 

 by Morris E. Leeds & Co. It should be written for by every col- 

 lege professor who has occasion to buy high-grade apparatus. 



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MORRIS E. LEEDS & CO. 



'^=aus«aad«s 



JAMES G. BIDDLE 



1034 Drexel Bldg., Philadelphia 





