Cutting It Fine - Microtomes in the Macleay Museum
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By Julian
Holland
Reprinted from Antiques in New South Wales, December 2000 - May 2001, pp. 8 + 17
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| Microtomes are devices
for cutting very thin slices to be examined under the microscope. They
are not everyone’s idea of a collectable. But consider their merits.
Microtomes are often fine pieces of mechanism. There are numerous
different designs. They have an interesting history. They provide a
bridge between technology and biology. The Macleay Museum at the
University of Sydney has a collection of microtomes which illustrate
these themes. First let us examine the origins of the instrument.
Compound microscopes were first developed in the seventeenth century. The first book substantially devoted to microscopy was Robert Hooke’s Micrographia published in London in 1665. With a finely sharpened knife Hooke cut very thin slices of cork and observed its porous structure, calling the holes ‘cells’. Others in the late seventeenth and early eighteenth century also prepared sections for microscopical examination but little detail is available. About a century after Hooke published his researches the first microtomes for systematically cutting specimens for the microscope were developed. John Hill, who was particularly interested in the structure of timber, designed an instrument a little like a pepper mill with a cam-shaped blade at the top for cutting sections of wood. In 1770 Hill published his description of the instrument which was manufactured commercially by Jesse Ramsden. A number of examples survive. Other designs of microtome were developed in the following decades but their use remained very rare until the second half of the nineteenth century. The expansion of universities and the development of government research laboratories, together with improvements in the optical qualities of microscopes, created an expanding market for microscopes in the nineteenth century. The scale of manufacture increased enormously in the closing decades of the century and microtomes likewise were being designed and manufactured for biological and medical work.
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| The Macleay Museum has
some 40 microtomes dating from the late nineteenth and twentieth
centuries. The simplest form is a small hand-held microtome made by the
French firm of Nachet dating from about 1890. This is included in the
current display, ‘Working with Microscopes’. The specimen in the
well of the instrument would be cut by drawing a hand-held razor across
the top plate. The specimen could then be raised for the next slice by
rotating the knob at the bottom.
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| A more elaborate version of the
same principal is seen in Figure 1. Here the microtome clamps to the
edge of a bench and has a fitting to supply carbon dioxide for
freezing the specimen to be cut. A pair of glass plates at the top of
the instrument guides the hand-held razor. This microtome was made by
the Spencer Lens Co. of the United States about 1920.
Figure 1: Freezing microtome by Spencer Lens Co., c. 1920 (Macleay Museum)
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| American manufacturing
expanded rapidly in the second half of the nineteenth century. This was
perhaps most obvious to Australian consumers in the mass-produced clocks
and watches being retailed locally. By the early years of the twentieth
century local agents in Sydney were importing machines, tools and
instruments – including microtomes – from American manufacturers.
One such firm was the Bausch & Lomb Optical Co. which began manufacturing microscopes in the mid 1870s and microtomes a few years later. The Museum has a sliding microtome of a type introduced by Bausch & Lomb in 1901. Rotary microtomes by Bausch & Lomb, dating from before the First World War, are also represented in the Museum. These larger microtomes used special sorts of knives held in a clamped mounting. Depending on the design of instrument the knife would be drawn through the fixed specimen or the knife would be fixed and the specimen move.
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| The expansion of scientific
laboratories in the German-speaking states of central Europe in the
nineteenth century encouraged the development of numerous microscope
manufacturers. Prominent among these were Carl Zeiss in Jena, Ernst
Leitz in Wetzlar and Carl Reichert in Vienna. Zeiss was making
microtomes by the 1870s but no example is held in the Macleay.
Figure 2 shows an impressive chain-driven sledge microtome of a design
introduced by Leitz in 1905.
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Figure 2: Sledge microtome by Leitz, c. 1910 (Macleay Museum) |
| A fine rotary microtome by
Zimmermann of Leipzig, dating from about 1910, is shown in Figure 3.
In this case the knife is held fixed and the specimen is brought down
across it by the motion of the handle wheel. This also controls the
motion of the ratchet-wheel mechanism for advancing the specimen for
successive cuts.
Figure 3:
Rotary microtome by Zimmermann, c. 1910
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| In the mid nineteenth
century some of the finest microscopes were being made in England. But
by the First World War the English market was significantly penetrated
by German manufacturers. It is perhaps surprising, therefore, that one
of the most important manufacturers of microtomes was English. The
Cambridge Scientific Instrument Co. grew out of the requirements for
physical and physiological instruments for University of Cambridge
laboratories in the late 1870s. In its early years an important part of
the firm’s business was the retailing of Zeiss microscopes and lenses.
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| Perhaps it was in conjunction
with this that the firm began manufacturing microtomes. Its
spectacular success was the rocking microtome designed by Horace
Darwin. This was first manufactured in 1885 and the basic design
remained in production for some 80 years. The original design can be
seen on the bench of the photographic room of the University’s
Medical School in a photograph taken about 1900 (Figure 4). A slightly
later version, dating from about 1900, is on display in the Museum.
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Detail of Figure 4.
(See below) |
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Figure 4:
Photographic Room, Medical School, University of Sydney, c. 1900
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| The Cambridge Scientific
Instrument Co. (or the Cambridge Instrument Co. as it became in 1924)
subsequently produced numerous designs of microtome. As the
‘rocker’ produced slightly curved sections, a flat-cutting rocking
microtome was introduced in 1899. The Museum holds an example of this
dating from about 1951. (right)
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Figure 5: Large sledge microtome by the Cambridge Instrument Co., c. 1927 (Macleay Museum)
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| The largest microtome
in the collection, shown in Figure 5, is also by the Cambridge
Instrument Co. It is a lever-operated sledge microtome of a design
introduced in 1909 which could cut specimens such as bones in sections
up to 40 square cm. This example is some 640 mm long (not including the
lever handle) and was made about 1927.
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| Today Japanese
excellence in optical and electronic goods is well established. This
technical achievement has long antecedents. The Museum holds two
microtomes of Japanese manufacture, a rotary instrument by Y. Takahashi
and a radial instrument by J. Oiso & Co. Both were made in the Hongo
district of Tokyo (where the University of Tokyo is located) and
possibly date from the 1920s.
For a collector with a taste for microscopes and microscope slides, or for precision machinery, it is worth keeping an eye out for microtomes. The principal historical reference is by Brian Bracegirdle: A History of Microtechnique – The evolution of the microtome and the development of tissue preparation (Second Edition, 1986). This contains a wealth of illustrations. Information on microtomes can also be found in some published museum catalogues of microscopy (including that of the Macleay Museum).
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Illustrations of microtomes reproduced courtesy of the Macleay Museum, University of Sydney Text © Julian Holland 2000-2005 |
