SCIENCE— ADVERTISEMENTS 



PRECISION OPTICAL INSTRUMENTS 



Made by ADAM HILGER. Ltd. 



We are now in position to again invite orders for liigh-claas instruments made by the British firm 

 of Adam Hilger, Ltd., — including Spectroscopes, Spectrographs, Spectrometers, Spectrophotometers) 

 Interferometers, Polarimeters, Refractometers, etc. 



This will be welcome news to those Scientists who are in need of such equipment, and are 

 familiar with "Hilger guaiity." 



JAMES G. BIDDLE 1211 Arch St., Philadelphia 



