SCIENCE 



New Series. Trr>TT\*A7- IVT a unxr 9ft 1 SQ7 Single Copies, 15 cts. 



-VOL.V. No.117. rULVAX, iVXA±tl.±l ZjU, i.OV I . ANNUAL Subscription, S5.00. 



Ziegler Electric Company, 



(Established 1882. Incorporated 1S94.) 



Physical, Scientific 



Chemical Apparatus, 



and 



Electrical Test Instruments, 



Optical Apparatus, etc. 



EXPERIMENTAL ^/^ >». PSYCHOLOGICAL 



"WORK EXECUTED TO J^ /^^^^m^. ^i APPARATUS, 



ORDER. a :> ^i^™y<g WL ^ TELESCOPES, 



SPECIAL APPARATUS VK M ks^^^^# ffl MEASURING 



CONSTRUCTED ^, '^fmmmsmfK'' jiff instruments, 



TO SPECIFICATIONS ^Stekw.. k J ^Jm^ X-RAY APPARATUS 



AND DRAWINGS. 'I/^^D^JTU^ TELEPHONES. 



Standard Barometers and Thermometers. 

 Apparatus imported duty free, for colleges. 



Correspondence invited. Illus. Catalogue, 240 pp. (price, $1.00), free to Teachers of Science. 



ZIEGLER ELECTRIC COMPANY, 



rSS'oJr'" BOSTON, MASS. 



