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Microscope Museum Collection of antique microscopes and other
scientific instruments |
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Microscope
494
(unassigned maker; Large drum microscope; mid 19th 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). 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. 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. While 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, similar to microscope 494. These drum microscopes are
relatively common and date from the early to mid-19th century.
Some instruments are signed by a retailer, while others, like microscope 494,
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. Microscope 494 came with its original wooden box. 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. |