Monocular compound microscope - 1910-1920 - Carl Zeiss Jena

Carl Zeiss Jena classic “Microscope Stand III D”.

Carl Zeiss Jena compound achromatic microscope, serial number 53699 (1911).

Tube and control knobs in clear varnished brass, tilting stand black-mottled brass. Tube extendable from 14 to 20 cm with scale.

Eyepiece: Carl Zeiss “4 Compens.-Eyepiece” [magnification 10x].
Objectifs, all original Carl Zeiss:
(1) AA, serial number 12762 [magnification 10x]
(2) DD, with removable front lens [magnification 40x?]
(3) “Homogeneous Immersion 1/12 D.A 13” with removable front lens [magnification ?]
Objectives with original brass bushings.

Round swivelable and centering stage with 2 clamps, covered with smooth ebonite (vulcanite or par rubber).

Abbe condenser with built-in conical iris diaphragm, lens system swing-out.
Extra swing-out iris diaphragm adjustable to the side for oblique/dark-field illumination.

Mirror with flat and concave side.

With original wooden case with key and metal label inscribed “E. Adnet Dépositaires à Paris Rue Vauquelin 26”.

Height max. 38 cm, weight 5 kg, with case 8.5 kg.

Mechanically and cosmetically in good condition, lenses reasonably good (immersion not tested), mirror on the concave side partly corroded, case solid but with light signs of use on the exterior.

Classic model, rare, with nicknames “Bierseidl” and “Jug-Handle” due to the distinctive handle included in the design to prevent a microscope being carried in the wrong way.
An important other innovation was the adoption of the improved fine focusing as devised by Max Berger in 1898, with a travel of 0.002 mm.

Several versions of this model were produced for various applications. This “Stand III D” was made from 1898 to the 1920s. The current specimen was delivered on February 10, 1911 to the firm E. Adnet in Paris, dealer in scientific equipment.