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Microscope Museum Collection of antique microscopes and other
scientific instruments |
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Microscope
525 (unassigned
maker; drum microscope; late 19th - early 20th century) Drum microscopes were apparently invented by German
makers in the early 1700's. However, it was Benjamin Martin who, in about
1738, introduced a format that became most popularized. Benjamin’s name
became associated with these types of microscopes, and they are to this day
often still referred to as 'Martin type' or ‘Martin drum’ microscopes. Simple
versions of the Martin type microscope were sold in large numbers during the
second half of the 19th century and early 20th century,
mainly with a French origin. The most common models, also with the lowest
quality, especially when sold in the 20th century, were models
like the ones illustrated in Figure 1 and the same microscopes with the
addition of a bullseye condenser (Figure 2). However, other versions of drum
microscopes were available from different makers and retailers (Figure 3),
like microscope 525. The original forms of drum microscopes had a sliding
coarse focus, although some versions had a rack and pinion focussing
mechanism. The stage of the basic drum microscope models allowed limited
access and movement to microscope slides, but some models had less obtrusive
designs such as an opening access to the stage from two sides (Figure 3), or
the use of a thin pillar to support the body tube rather than using an
extension of the basic outer tube housing upwards, like in microscope 525.
Most drum microscopes were sold with a single objective, but often the French
objectives were divisible and sometimes extra objectives and other
accessories were supplied. Some drum microscope models allowed for
inclination (Figure 3B). The earlier versions of drum microscopes
were sold in heavy hardwood boxes, but the later, especially twentieth
century models, were often sold in lower quality and thin pine boxes. At the same time that some of these toy drum
microscopes were being sold, more substantial and complete models that could
be used for more serious work were also available. These included examples
made by makers such as Nachet, Oberhauser,
Hartnack and by some English makers through much of
the 19th century, though less commonly as the century progressed.
Figure 4 illustrates an example of a Large Improved Compound Microscope.
These drum microscopes are relatively common and date from the early to mid 19th century. Some instruments are signed
by a retailer, while others are unsigned. Most likely these microscopes were
made for the trade and not necessarily by the firm identified by the
signature. Versions of these instruments were produced with and without the
rack and pinion focusing mechanism. Figure 1. Several versions of
drum microscopes sold during the second half of the 19th century as
engraved in antique catalogues of different makers and retailers: (A) Spencer
Browning & Co (1857); (B) Negretti & Zambra (1859, 1870s and 1885); (C) William McAllister
(1867); (D, E) James Queen (1870 and 1872); (F) Miller Bros (1879); (G) R
& J Beck (1882); James Queen & Co (1890). Figure 2. Several versions of
drum microscopes as in Figure 1 but including an bullseye lens, sold during
the second half of the 19th century as engraved in antique
catalogues of different makers and retailers: (A) Spencer Browning & Co
(1857); (B) Negretti & Zambra
(1859); (C) F & J Amadio (1864); (D) William McAllister (1867); (E) James
Queen (1870); (F) James Queen (1870 and 1872); (G, H) Negretti
& Zambra (1870s, 1885); (I) Miller Bros (1879). Figure 3. Different versions
of drum microscopes as engraved in an antique catalogue of B Kahn & Son
(c. 1890). Figure 4. An engraving of the
English Large Improved Compound Microscope as shown in the 1848 Pike's
Illustrated Descriptive Catalogue of Optical, Mathematical and Philosophical
Instruments. |