8 
R. & J. BECK'S 
MICROSCOPES 
No. 13c BINOCULAR “NATIONAL” MICROSCOPE. 
The Binocular National Microscope, with rack-and-pinion coarse-; 
and screw fine-adjustments, concentric rotating stage, concave mirror, 
rack and pinion adjustment to body of instrument for varying the 
distance between the eye-pieces for Stereoscopic vision. Two pairs of 
eye-pieces, 2-inch, f-inch, and J-inch object-glasses, side condensing 
lens on stand, iris diaphragm, forceps, pliers, and glass slip with 
ledge. Packed in polished mahogany case with lock and key and 
handle £17 17 0 
Double Nose-piece, 16s. 6d. ; Triple Nose-piece, £2 extra. 
NEW 1/12 INCH OIL-IMMERSION OBJECT-GLASS, £5 108. 
NEW FULLY ILLUSTRATED CATALOGUE FREE ON APPLICATION. 
R. & J. BECK, Ltd., 68 Gornhill, London, E.C. 
FACTORY: LISTER WORKS, KENTISH TOWN, N.W. 
