Early 20th century cased brass monocular microscope manufactured c1925 by Ernst Leitz of Wetzar, Germany and retailed by Ogilvy & Co, London. Solid lacquered brass monocular microscope with black enamelled horse-shoe foot. Extending main barrel housing eyepiece lens. Revolving nosepiece or turret housing three objective lenses. Rack and pinion wheel for coarse focusing and micrometer wheel for fine focusing. Circular rotating stage with slide-clips and two centring screws for adjustment on both X and Y planes. Sub-stage there is a condenser lens and iris diaphragm, above a double sided planar/concave mirror with height adjustment wheel. Main barrel stamped Ernst Leitz Wetzar No 193384. In original fitted dovetailed case with working lock and key. Manufacturers card to inside door, specifying magnifications for the two eyepiece and three objective lenses as originally supplied with the microscope (with serial number 193384). The fitted case houses slide-out racks holding numbered eyepiece lenses 2 & 4 and objective lenses 3, 6 & 8 (in brass canisters) as well as a slide-out lidded box for accessories. Fully extended the microscope is approximately 41 cm in height. Case measures 33.5 cm height by 17.5 cm width and 19.5 cm in depth.
 
The original company was established in Wetzlar, Germany by Karl Kellner in 1849. Initially the company’s main production was in telescopes however, within a few years microscopes had become their primary focus. In 1865 Kellner hired the engineer Ernst Leitz, who became a partner – fully acquiring the company in 1869 and renaming it the Optical Institute of Ernst Leitz. The company’s reputation for quality optical instruments grew rapidly and they added several new instruments to their range. The company continued in family ownership with Ernst’s grandson Günther, establishing the Leica camera factory in Canada in 1952. Competition from Japan in the 1970s resulted in merger with Wild Heerbrugg to form the Wild Leitz Group. In 1988 the group split-up, forming Leica Cameras as a spin-off with the remainder of the holding merging with the Cambridge Instrument Company in 1990, creating the Leica Holding B.V. group.
Ogilvy & Co originally of 20 Mortimer Street, London W1 and with workshops at Kenton Street, were makers of microscopes and other scientific apparatus. In c1925 they relocated to 18 Bloomsbury Square where they were also British agents for Leitz until c1928.