( 10 ) 



GEEATLY REDUCED PRICES 



OF 



OBJECT-GLASSES MANUFACTURED BY 



R. & J. BECK, 



68, CORNHILL, LONDON, E.G. 



PRICES OF BEST ACHROMATIC OBJECT-GLASSES. 



ECONOMIC ACHROMATIC OBJECT-GLASSES, 



Appuoable to all Instbtjmekts made •with the Universal Screw, 



No. 



150 

 151 

 152 

 153 

 154 

 155 

 156 

 157 



Focal length. 



3 inches 

 2 inches 

 1 inch . 

 § inch . 

 I inch . 

 ^ inch . 

 i inch . 



Angle 



of 

 aper- 

 ture, 

 about 



38 



80 



no 



no 



180 



Price. 



s. 











5 



5 



5 



5 



3 10 

 6 



Maqnifting-power, 



with 6-inch body and 



eye-pieces. 



No. 1. No. 2. No. 3, 



46 



90 



170 



250 



350 

 654 



Sevised Catalogue sent on application to 

 It. & J. BJECK, OS, Cornliill. 



