Accession No
1537
Brief Description
achromatic compound microscope, by Carl Zeiss, German, 1890 (c)
Origin
Germany; Jena
Maker
Carl Zeiss
Class
microscopes
Earliest Date
1890
Latest Date
1890
Inscription Date
Material
metal (steel, nickel, silver, brass); glass; wood
Dimensions
height 340mm; depth 160mm; breadth 125mm box height 388mm; depth 213mm; breadth 234mm 3 eyepieces: all diameter 28; one length 102mm; one length 51mm; one length 34mm stage length 153mm; breadth 119mm; thickness 29mm
Special Collection
Provenance
Purchased from D.M. Nesbit in Southsea in 17/01/1974.
Inscription
‘Carl Zeiss
Optische Werkstatte
Jena
No. 15500’
Description Notes
Black foot with steel body and nickel silver finish; horse shoe foot; double pillars to joint; circular stage upper plate graduated 0-(360) by 10 to 1; clamping screw; fine motion screw; racked tail piece for substage; substage condenser; swinging iris diaphragm with rack; swinging plano/concave mirror. Pillar to cranked limb; 2 coarse focus screws either side of body; fine focus screw, with conical head at top of pillar graduated 0-(25) by 5 to 1; index on back of limb; screw fit eye piece collar; 2 slots in body for sliding micrometers and polarising apparatus; 3 Zeiss objective cases for B, DD, and AA objectives; 1 objective by the ‘Spencer Lens Co.’ ‘1.8mm Homog. Immer’ with case; one other case; 2 push fit eyepieces ‘2’ and ‘4’; 1 ‘Mikrometer’ ‘3’; all signed ‘Carl Zeiss, Jena’; analyser; mount for substage stops; 2 push fit stops; [erecting] eyepiece; polarising apparatus including slides for the slots in the body. Fully mechanical stage. Fitted wooden case with brass handle.
Condition: good
References
Events
Description
When light travels through an ordinary lens each colour is bent through a different angle. In a microscope this causes what is known as chromatic aberration, whereby a spectrum of colours will appear around the image being viewed. Chromatic aberration was a big draw back when using early versions of the compound microscope.
Chromatic aberration was overcome due to the important work by Lister in 1830 who developed the achromatic lens for microscopes. The new type of lens prevented colour separation by combining two lenses made of different types of glass. The first lens that light passed through would split the colours and the second lens acted to bring the colours back together again. This produced a much sharper and clearer image than was previously achieved.
In the Victorian period the achromatic microscope became a vital tool in medical and scientific research. Improvements to the optical performance of the microscope saw developments in the design and construction of the microscope. The microscope became sturdier and could focus to a finer level.
Scientific instrument makers in the Victorian period who improved the rigidity of the optical tube and the focusing ability of the achromatic microscope include Andrew Ross, James Smith and Hugh Powell.
FM:39907
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