1033 - E. Leitz Wetzlar, Brass Microscope in its Original Case with Certificate, Dated 1892

E. Leitz Wetzlar, Brass Microscope in its Original Case with Certificate, Dated 1892 Brass and lacquered metal, wood. Microscope with a horseshoe foot, a straight brass pillar on a stepped base, a curved tube carrier with coarse and fine focus, a round stage and a pivoting illuminating mirror, the tube with a nosepiece carrying three objectives. Marked and numbered on the foot „E. Leitz Wetzlar No. 24637". In the lid of the case an inserted card, filled in by hand with the microscope number, the note „Vergrösserungen bei 160 Mm. Tubuslänge" and the date of issue „Wetzlar, den 25 XI 1892". As accessories four eyepieces in their own wooden holders, brass canisters with screw caps inscribed „Oel Immersion 1/12 Tubusl. 170 mm E. Leitz", „7 E. Leitz" and „3 E. Leitz", the eyepieces inscribed among others „5x FO", „8x Ernst Leitz Wetzlar" and „12x Ernst Leitz Wetzlar", together with a black canister bearing the lozenge logo „Leitz Wetzlar" and one diaphragm disc. The original case with an engraved number, lockable, key present, a fitted metal handle on top. Good condition commensurate with age, traces of use particularly on the stage, the edges slightly scuffed. Microscope h. approx. 32 cm Ernst Leitz took over the Wetzlar optical institute in 1869 and built it into one of the leading makers of microscopes; in 1907 the hundred thousandth instrument left the works. Every microscope was accompanied by a card on which the serial number and the date of issue were entered, so that the year of manufacture can be established beyond doubt. Oil immersion, in which a drop of cedar oil is placed between specimen and front lens, was the most demanding technique available around 1890 and belonged to the equipment for bacteriological work. Sets of instrument, original case, accessories and the accompanying card are rare, because the papers are almost always lost.