/<5 3 Z6' 



SCIENCE 



New Series. "PpTnAV F-p-RRTTA-RV 17 1 8QQ Single Copies, 15 CTS. 



VOL.IX. N0.216. TKiDAi:, TiiJiKUAlvY 1/., lOVV. Annual SUBSCRIPTION, S5.0C. 



Clieniical and Physical Apparatus 



CHEMICALLY PURE ACIOS AIVD 



SOLE AGENTS FOR 



SCHOTT & GENOSSEN, JENA NORMAL GLASS 

 SCHLEICHER & SCHULL'S CHEM. PURE FILTERS 

 SCHMIDT & HAENSCH'S OPTICAL APPARATUS 

 MAX KOHL'S PHYSICAL APPARATUS 



EMER& AMEND 



205, 207, 209, 211 Third Ave. 



NEW YORK 



