Polariscopes and Related Instruments

Polariscope with fixtures (lacquered brass) mounted between two steel rods (length 42.2 cm). Circular base (lacquered brass, diameter 12.3 cm) mounted on square (22 cm) mahogany base (height 10 cm) with drawer. Fixtures include mirrored base, glass polarizing plate, circular stage, 3 condensing lenses, specimen holder and black glass analyzer plate.
Signed on drawer "HANS HEELE | Werkstätten für | PRÄZISIONSOPTIK & MECHANIK | BERLIN, 0.27", 1st half 20th century.

Polariscope (lacquered brass) with fixtures mounted between two rods. Circular base mounted on square (18.7 cm) mahogany base (height 6 cm) with drawer. Fixtures include mirrored base, glass polarizing plate with graduated wheel and pointer, graduated rotating and tilting glass specimen stage and a rotatable analyser prism with vernier read-out. Total height: 51 cm.
Signed "Jules Duboscq | à Paris", 2nd half 19th century.

Stone/marble base 15 cm diameter with inset circular mirror, overall instrument height is 41 cm.  Two parallel steel pillars carry a rotatable Nicol prism sitting in a 360 degree graduated circle, three swing away condenser lenses, and a swing away gimbaled holder at mid height with outer graduated circle.  There is also a lower rectangular tilting glass plate.  An accessory is a removable adjustable dark mirror that will sit in either the inset over the base mirror or in the upper graduated circle when the Nicol prism assembly is removed.

Polariscope (lacquered brass, oxidized brass) fixed on a circular base (total height 33 cm). Reflecting mirror (9.5 x 12.5 cm), pile-of-plates polarizer, condenser, and objective, focusing optics and Nicol prism analyzer.
Unsigned, but almost certainly made by Steeg and Reuter in Bad Homburg vor der Höhe, first half 20th century.

Polariscope (lacquered brass, nickel plated brass, oxidized brass) with maple case also used as base (30.8 x 13 x 9.7 cm; total height 35.8 cm). Reflecting mirror, pile-of-plates polarizer, condenser, round stage, objective, focusing optics and Nicol prism analyzer.
Unsigned, first half 20th century.

Large lacquered brass polariscope with numerous accessories to demonstrate and investigate polarisation phenomena standing on a large base (23 cm diameter) with a tall column supporting the body of the instrument (length 66 cm) on an adjustable mount. The mount allows the polariscope to be inclined and then fixed in position with a knurled wheel.
The body in constructed in such a way that all of the parts are interchangeable. Each section has a silver collar onto which is engraved a scale. Where the scales fit the corresponding collar has an engraved arrow to show the degree of rotation.

Polariscope tube (lacquered brass) with rack and pinion focusing. Black painted cast iron base, mirror on mahogany support. Nicol prism polarizer with 360-degree scale, condensing lens, Nicol prism analyzer, ocular. Height of the instrument 36 cm.
Signed on the polarizer scale "R. FUESS | BERLIN", serial number "6776" on base, first half 20th century.

Polariscope - optical bench to demonstrate and investigate polarization phenomena in crystals by means of projection.
Lacquered brass polariscope and accessories on cast iron base Height to top of instrument with stand closed is 50 cm. It can be extended to 65 cm by the slip joint in the pillar. Length is 40 to 45 cm depending on where the pieces are mounted on the slide brass rail. No further accessories.
Signed "M^on. Jules Duboscq Ph. Pellin, Paris" on the rail, end 19th century.

Polariscope - optical bench with numerous accessories to demonstrate and investigate polarization phenomena in crystals by means of projection.
Lacquered brass polariscope and accessories on cast iron base (height:  35 cm) with brass rail (length: 34.6 cm), total height of the instrument: 48 cm. The accessories are stored in a wooden box (44.7 x 22.9 x 13.6 cm).
Signed "F. Pellin, Paris" on the rail, early 20th century (1912 or later)

Set of 24 polariscope specimens mounted in square paper covered cork plates (3.5 cm), with circular glass support (diameter 1.3 cm, one of 0.6 and one of 2.4 cm). The names of the samples are printed on the paper cover. In compartmented black cardboard case with plush lined cardboard cover.
Signed on the paper covers "Optisches | Institut | von | Dr. STEEG & REUTER | in | Homburg v.d.H.", first half 20th century.

Two thin sections of transparent tourmaline mounted in cork in independently rotatable oxidized brass disks (diameter 2.8 cm) at the ends of a pair of spring tongs (length 15 cm).
Unsigned, first half 20th century.

Mahogany disc (diameter: 7.5 cm) rotatable between thin sections of tourmaline (mounted in ivory eyepieces); 10 crystal sections are mounted to show optic-axis figures: topaz, aragonite, gypsum, sulphate of barytes, carbonate of lead, fluor spar, quartz, borax, nitre, calc spar.
The instrument (total length 18 cm) rests in its plush-lined cardboard case (8.2 x 19.3 cm) with a label reading "Toermalijn | platen | (opt. assenbeelden)" i.e. "tourmaline sections (optic axis figures)".
Unsigned, second half 19th century.

Stauroscope for the measurement of extinction angles in crystal sections. Reflecting glass plate polarizer (10.8 x 10.8 cm) on a mahogany base (21 x 13.5 cm); graduated half circle (diameter 9.5 cm) on the lacquered brass body tube (length: 19 cm).
unsigned, but probably Böhm & Wiedemann, München