No. 53 906. 



Refraction and Reflection. 



495 



53892. 1: 10. 



53 898. 1 : 10. 



53 895. 1 = 2. 



53.892. Demonstration Apparatus for the Refraction of Light by convex and concave lenses, s. d. 

 Figure, after Neumann (Ztschr. f. d. phys. "u. chem. U. 8, 1895, p. 268) 1. 16. 



The apparatus comprises two angles formed of brass strips (incident and refracted ray). The 

 149 angle is for the convex and that of 154 for the concave lens. 



The variable size and width of image can be demonstrated with the aid of the apparatus. 



53.893. 2 Slabs with Pair of Pulleys and velvet Supports, for showing mechanically the deflection 



of the luminous rays in prisms, plates and lenses (M. P., 8 th Edn., II, 1, Fig. 370) . 1. 12. 



53.894. 6 Lenses in simple Case, Figure, plano-convex, bi-convex, concave-convex, plano- 

 concave, bi-concave, convex-concave, 50 mm diameter, Figure 0. 10. 



53.895. 6 Lenses in case, Figure, plano-convex, bi-convex, concave-convex, plano-con- 

 cave, bi-concave, convex-concave, 65 mm diameter 0. 16. 



53.896. 6 Lenses in Case, smaller: plano-convex, bi-convex, concave-convex, plano-concave, 

 bi-concave, convex-concave, 40 mm diameter, in mount with metal hafts 1. 10. 



53.897. - - idem, and, in addition, 2 Cylindrical Lenses and 1 Achromatic Lens, also 2 Stands 2. 16. 



."..'i.sux. Piano-Convex-Lens 200 mm diameter, Figure, on tripod, for demonstrating 

 spherical aberration and chromatic aberration of the refracting light-rays with the aid 

 of two diaphragms, one with a number of holes on the edge and one with round hole 

 in centre 2. 10. 



.">.'!, *99. Achromatic Lens System, on Stand, one lens fixed and the other movable in hinge; 



diain. 30 mm, focal length 30 cm 1. 5. 



r>:;.'.Mto. --idem, 40 mm diameter, focal length 30 cm 1.10.0 



Achromatic Lenses, in mount with haft, without stand. 



List No. 53,901 53,902 53,903 53,904 53,905 



Diameter mm 50 60 70 80 100 



Focal Length mm 300 500 500 500 800 



1.0.0 1.10.0 2.0.0 2.10.0 3.12.0 



53.906. Stand for above . . 0. 5. 



, 



Cl. 1348, 1349, 

 1353, 1352. 



