Nuremberg-type microscopes, ca.1800.
The term "Nuremberg microscopes" refers to a group of microscopes with very distinct stylistic characteristics, originating in areas of present-day southern Germany: Bavaria and the "Black Forest" area of Baden-Württemberg. Toy manufacturers specializing in woodworking have operated in these areas for centuries. The city of Nuremberg was known for its centuries-old tradition of fine engineering, which led to its nickname in the 16th century as the city of "Makers of the Compass". These manufacturers produced portable sundials, and in the 18th century it was a center for the production of toys and visual glasses in the German countries. The toy district in Bavaria, near Nuremberg, is particularly well known. It appears that the microscopes were offered as an additional product, sometimes adjacent to simple refractory telescopes. These were simple and inexpensive microscopes and telescopes made of lightweight materials, mainly from light fruitwood and cardboard, that did not pretend to be in line with the professional and very expensive brass instruments of their time, both mechanically and at their optical level.
In 20th-century research, there was a lively discussion about the period of production of Nuremberg's famous wooden and cardboard microscopes, many copies of which have been preserved in science museums and private collections. They were originally attributed to the second half of the 18th century. But studies from the 1980s onwards have shown that most of their production was during the late 18th century and into the first half of the 19th century, while telescopes continued to be manufactured into the first decades of the 20th century. The microscopes typical of this industry are a special category in the history of the microscope. The devices, which many of the historians of scientific instruments refer to as toy microscopes, could have been made at low cost and in large numbers and were successfully sold in the German lands of the era and beyond. Their optical quality was very basic and subject to considerable distortions (aberrations), and due to their defective optical properties were hardly suitable for serious microscopic examinations, even in their time.
In their designs, the Nuremberg Microscope was inspired by some of the typical designs of the English microscope of the mid-18th century. Three main types can be identified: a small model based on the pocket microscopes of Benjamin Martin, the brilliant British manufacturer of the second half of the 18th century, based on a tubular body that combines the mirror and the stage, topped by a cylinder through which the lens tube slides. In the Nuremberg version, this concept was copied to combine an elongated walnut box containing the mirror and above it two simple rectangular openings for inserting a wooden slider with a row of round holes in which the samples were placed between thin glass discs or mica plates, and above it a cardboard roll with wooden reinforcements. The lens tube that focuses on the paraffin is made by sliding it up and down inside the cylinder. This device is sometimes also called the "sentry-box microscope". Although this design was inspired by Martin's "pocket microscope" invented 50 years earlier and developed during the 19th century to create the "Continental Microscope" of major manufacturers in France and German countries. But in the Nuremberg version this is a very crude and simple version of the original that seems like a rustic rendition of the general outline.
Another model is based on the popular design of Edmund Culpepper from the beginning of the 18th century, which was a great success and continued for a hundred years into the first decades of the 19th century. This design is characterized by the structure of a double tripod. In the Nuremberg version, a center of a round wooden base made of a lathe was set, which had an adjustable mirror on its axis, and three thin legs rose from its edges, which were also made of a lathe. These were supported by another round wooden frame into which a tube was fitted with a simple device for inserting the aforementioned wooden slide, and above it a cardboard cylinder designed to receive the lens tube. Nuremberg microscopes of this type are clearly rather coarse copies of the tripod microscope. "Culpeper") of the 18th century goes back to the early 19th century. The original tripod microscopes, also produced in large quantities for the British middle class, were produced for a public interested in natural history but without in-depth scientific ambitions or means to purchase "real" and very expensive microscopes. This, both the English original and the more clumsy copies made of it in Bavaria, represent an important aspect of the history of science - the emergence of popular science towards the end of the 18th century.
The third model is based on the microscope model designed by John Cuff in the mid-18th century. It is based on a wooden box with an accessory drawer on which is placed a pillar that carries all the components of the system: the mirror, the stage, the focusing system and the lens tube. The overall design was the same for all three models: the devices were made of light wood, probably fruit wood, while the tubes that were pulled out of each other were made of cardboard covered with colored paper. Except for the slides, the microscopes usually had no additional accessories. Storage boxes for microscopes are extremely rare.
The Nuremberg microscopes known so far do not have the usual manufacturer's engravings, but brand marks, that is, letter combinations engraved on the wood - especially on the lower side of the base. Only a few brands are known so far, although they cannot be attributed to specific manufacturers. The most common combinations of letters IM and JFF, the first is sometimes attributed to a manufacturer or marketer who identified himself as Junker, Magdeburg. But in all cases, the signatures seem to refer to specific marketers and not specific manufacturers. It is very likely that as was customary in the 18th century, the various wooden parts of the microscopes were mass-produced by specialized workshops, as were the lenses and cardboard tubes, and these were assembled and sold by the marketers under their name. This is also implied by the identity of the optical tubes, which can be transferred from one type of microscope to another, suggesting co-production.
It is difficult to accurately date the Nuremberg microscopes. Documents from manufacturers or marketers, or other historical sources are unknown and do not appear to have existed. Turner believes that these microscopes were created mainly in the first half of the 19th century. But this theory is contested by the catalogue of Catel (1790), where the tripod and the "sentry box" types appear alongside hundreds of other toy instruments in his "Mathematical and Physical Art Cabinet", which have been most likely existing in the market for a few decades. Peter Friedrich Catel (1747-1791) was a gifted and inventive precision mechanic from Berlin who brought the first illustrated goods catalogue onto the market in 1790. His pedagogical approach to the invention of toys and his business sense made him known far beyond Germany. Being the puzzle and toy catalog of P.F. Catel, founded in 1780. Hundreds of toys are minutely described. There are magic squares and interlocking wooden puzzles and also optical toys, doll houses, shuttle cocks, a bowling alley and pins, a toy apothecary shop, playing cards, swimming ducks, and much more. "This is a most surprising book -- in its modernity, in its modesty (the lengthy preface by the publisher concerning Catel's business and its business philosophy is entirely unpretentious) and in its rarity" (Princeton, Cotsen Children's Library catalog).
On the other hand, Petrie (1896) states in his book The Microscope that it is still possible to buy cheap Nuremberg microscopes of the "sentry box" type from Nuremberg opticians. This information is highly unlikely, as towards the end of the 19th century there were many cheap brass microscopes made in France that were mass-traded throughout Europe and North America and were far superior to the Nuremberg model mechanically and optically. All of these microscopes were produced in a more or less uniform style, with slight changes in the decorations, probably for several decades. It can be stated in generalization that most of the production of Nuremberg microscopes took place between the years 1750-1830, mostly around 1800.
However, as strange as it may be, in several cases these Nurremberg microscopes, especially of the type seen here, had their fair share in the advance of scientific research. Despite their rustic design and very elementary optical performance, in some cases they turned to become useful in the hands of some prominent scientists in the early stages of their career. A Nuremberg Tripod microscope is known to be used by Jan Evangelista Purkyně (1787-1869) in his early studies of the large neurons found in the cerebellum, called after him (Purkinje cells), the Purkinje fibres (the fibrous tissue that conducts electrical impulses from the atrioventricular node to all parts of the ventricles of the heart), and other discoveries (Chvátal 2017). A similar microscope is recorded as being used by Christian Gottfried Ehrenberg (1795-1876), the German naturalist, zoologist, comparative anatomist, geologist, and microscopist, in his work on infusoria for which he is primarily remembered. Ehrenberg began this work just after he returned from a voyage to Siberia with Alexander von Humboldt, on which he had gathered a large collection of zoological and botanical specimens. In his memoirs he refers to "only a very incomplete thirty-shilling wooden compound microscope from Nuremberg" with which he began his work (Ehrenberg 1837; Jardine 2009).
Catel, P.F. 1790. Mathematisches und physikalisches Kunst-Cabinet, dem Unterrichte und der Belustigung der Jugend gewidmet. Berlin: F.L. Lagarde.
Chvátal, A. 2017. Jan Evangelista Purkyně (1787-1869) and his Instruments for microscopic research in the field of neuroscience. Journal of the History of the Neurosciences, 26, 238–256.
Ehrenberg, C. G. 1837. On the origin of organic matter from simple perceptible matter, and on organic molecules and atoms; together with some remarks on the power of vision of the human eye. Scientific Memoirs, 1, 555–583.
Jardine, B. 2009. Between the Beagle and the barnacle: Darwin’s microscopy, 1837–1854. Studies in History and Philosophy of Science, 40, 382–395.
Nuremberg microscopes in the toy catalogue by Catel (1790).