498 



Refraction, Total Reflection. Optical Measuring Instruments. Spectrum Analysis and Synthesis. NO. 53931- 



53 932. 1 : 6. 



53 933. 1 : 6. 



s. (1. 



lo. 10.0 



53.931. Optical Apparatus after Mach, Figure, as improved by Kolbe, for explaining 

 the phenomena of reflection and refraction with visible beams of light (Ztschr. f. d. 

 phys. u. chem. U. 7, 1887, p. 77) 



The apparatus consists of a box 1 in long, with iron legs, the walls being formed by glas> plates. 

 and in which an optical bench is set up. The sliders of the bench can be adjusted from outside. 

 A graduation is provided on the front wall and permits of reading the distances between lenses. By 

 inserting various gratings and frames with differently arranged coloured glasses at the narrow end, 

 the experiments are carried out in the box, which is filled with smoke (reflection of spherical mirrors, 

 refraction of light in lenses and prisms, demonstration of chromatic and spherical aberration). 



The following pertain to above: 3 lenses in mounts, 120 mm diam.: 2 ground mirrors, convex 

 and concave, 120 mm diam.; 1 prism, 1 screen, 3 gratings of different fineness, 1 small plane mirror 

 on adjustable stand, 2 sliders with coloured glass, 2 cover plates. 



53.932. Supplementary Apparatus for Refraction and Total Reflection in Liquids, Figure, 



and Stand with 2 adjustable plane mirrors, for Apparatus No. 53,931 3. 0. 



The apparatus is provided on front side with circular graduation, degree and sine graduation. 



53,932a. Fillet with 2 lens mounts and small glow lamp, also lens mount on base, after (irim- 

 sclil, for measuring the radius of curvature of a convex lens; for Students' use (K. (irim- 

 selil, Ausgewahlte pliysikal. Sehiileriibungen, Fig. 13) 



53,932b. 30 Lenses, arranged in dioptres, in box, for use with preceding apparatus and with 

 apparatus for determining focal length. No. 53,932c, and the Grinisehl Diffraction 

 Apparatus No. 54,549, etc 1. 10. 



0. lo.o 



Cl. 1369, 1360, 1367. 



