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SCIENCE 



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ELEVENTH EDITION 



THB MICROSCORE, 



en introduction to Microacopic Methods and to Histology, by 

 BiMON Henrt Gage of Cornell University. The 11th edition 

 has eight pages of new matter and corrections, otherwise it ll 

 lllie the 10th ed. Price $2.00 postpaid. 

 COMSTOCK PUBLISHINQ CO., Ithaca, N. Y. 



PROVIDENT 1 EACHERS' AGENCY 

 120 Tremont Street BOSTON, MAS&. 



We enroll and we recormiiend teachers and officerfl 

 for public and private schools, for Dorrtial and tech- 

 nical schools, arid for colleges and universitiea. 

 Vacun<'ies now for itiimcdiate service and for 1914- 

 15. Director, JAMES LEE LOVE, formerly of 

 Harvard Faculty. 



FOR SALE 



A«tronointcal Telescope — 6-inch (Brasliear) objective, 

 90 inch focus, with finder ; Dioumed on iion column heving 

 fine adjuptTnent in azimuth— circles rfadingby vernier to 1 

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 governors, driven by ^Veighls— Slow motion ftttbchrnents in 

 both Right Ascension and Dcrlinatinn — Ten eye pi-ceg. with 

 dingonal prisms for both star and solar observations. Price., 

 SfJT.S. Also Fauth mif romtter with p' sition rin le, S175. 



STI-: HFN LOTN'FS. ^i WrII ."Street. NFW YORK. 



Buy Science Apparatus 

 Direct From tiie Factory 



Write for the Chapco Purchase Guide No. 11 

 and note the remarkable savings on high grade 

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 is sold direct from factory to schools. **> 



Chicago Apparatus Co. 55 s. Clinton St. Chicago 



We.hrsen Heavy Current Influence Machine 



Machine with two 50 cm. revolving disks delivers 600 micro-amperes, with 

 spark 30 cm. long. 



Tor further details 

 T\nte to 



James G. Biddle 



Special Agent 



1211-13 4rch Street, 

 PHILADELPHIA 



^^'■"^^ .ii.i l ll^lll] im.. 



