(Didactic Division)

Optical

Prism Glass Equilateral

Non-optically worked with polished faces, edges slightly bevelled. Nominal angles 60 x 60 x 60 deg.
Size
25 mm.
38 mm.
50 mm.

Prism Acrylic Equilateral

Clear acrylic polished surfaces, 60 x 60 deg.
Length
Face
38 mm.
38 mm.
50 mm.
50 mm.
63 mm.
63 mm.

Pair of Narrow Prism

Designed to provide a progression of ideas from the principles of refraction in prism to the properties of lenses. Each glass prism is in the form of a narrow isoceles triangles 10x60x20mm. base, heights, thickness. When place base to base a convex lens may be simulated, and a concave lens when vertex to vertex.

Lenses, Set of Six

50 mm. diameter with ground and polished faces and ground edges. One each of double convex, plano-convex, converging concave-convex, diverging concave-convex, double concave, plano-concave. Supplied in box.

Magnifier Reading Glass

In metal frame and handle, chrome plated, packed in cardboard box.
Diameter
50 mm.
50 mm.
50 mm.
60 mm.
60 mm.
60 mm.
75 mm.
75 mm.
100 mm.
100 mm.
125 mm.
150 mm.
Focal Length
10 cm.
10 cm.
20 cm.
10 cm.
15 cm.
20 cm.
15 cm.
20 cm.
15 cm.
20 cm.
30 cm.
30 cm.
Magnification
3.5x
3.5x
2.25x
3.5x
2.5x
2.25x
2.5x
2.25x
2.5x
2.25x
1.83x
1.83x

Magnifier Reading Glass

In metal frame and bakelite handle, chrome plated, packed in cardboard box.
Diameter
50 mm.
50 mm.
50 mm.
60 mm.
60 mm.
60 mm.
75 mm.
75 mm.
100 mm.
100 mm.
Focal Length
10 cm.
10 cm.
20 cm.
10 cm.
15 cm.
20 cm.
15 cm.
20 cm.
15 cm.
20 cm.
Magnification
3.5x
3.5x
2.25x
3.5x
2.5x
2.25x
2.5x
2.25x
2.5x
2.25x

Concave Mirror, Glass

Optically worked, silvered back with protective coating.
Dia. mm
50
50
50
50
50
50
75
75
75
75
75
75
Focal Length mm.
50
75
100
150
200
300
50
75
100
150
200
300

Convex Mirror, Glass

Optically worked, silvered back with protective coating.
Dia. mm
50
50
50
50
50
50
75
75
75
75
75
75
Focal Length mm.
50
75
100
150
200
300
50
75
100
150
200
300

Concave Mirror, Glass

Optically worked, silvered back with protective coating.

Glass Slabs

Clear glass with ground ends and optically worked faces.