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The oldest microscope in the museum

In the store-rooms of the museum, we recently discovered a small microscope made around 1750. The "I. CUFF Londini Inv. & Fec." inscription (which is Latin for "designed and made by I. Cuff of London") is that of John Cuff (1708-1772), a talented instrument maker whose shop was to be found "directly against Serjeant’s-Inn Gate in Fleet-Street." Maps of the period indicate that this address was just three doors away from Crane Court, home of the Royal Society of London, an early and important scientific organization. While craftsmen such as Cuff were seldom elected to Fellowship in the Society, they could attend meetings and interact with gentlemen who might appreciate and afford their wares.

Wooden box lined with green velvet containing microscope parts

At a meeting of the Royal Society in the winter of 1738-1739, Cuff met Johann Nathanael Lieberkühn, a German physician who had come to England to promote two instruments he had recently devised. One, the solar microscope, used sunlight to throw an enlarged image of a small specimen onto a wall on the other side of the room. The other, the microscope for opaque objects, used a silvered mirror to throw light onto the objects under investigation. After watching Lieberkühn's demonstration, Cuff took great pains to improve these instruments and "bring them to perfection"—the words are from Henry Baker, Fellow of the Royal Society and author of The Microscope Made Easy (London, 1742), a popular text that went through several editions.

It was also through the Royal Society that Cuff hooked up with Abraham Trembley, a Swiss naturalist whose observations of small aquatic creatures that could regenerate lost parts was creating a buzz within the scientific community. Martin Folkes, President of the Royal Society, showed some of Trembley's polyps (as the creatures were known) to large and enthusiastic audiences in March 1743, and probably used his Cuff microscope for this purpose. When Trembley visited London in 1745, he asked Cuff to make a microscope that would facilitate observations of aquatic creatures as they moved about. By 1747, Cuff was boasting of "The AQUATIC MICROSCOPE" which was "invented by him for the Examination of Water Animals."

Microscope set up on case

Our microscope is of this sort. It is a brass instrument with a single lens that can move in three directions (right and left; forward and back; up and down), a large stage, and a sub-stage mirror. A wooden box covered with fish-skin serves as a base for the microscope when in use, and as protection when not. There are also several extra lenses as well as sliders made of ivory. The provenance, alas, is unknown.

In 1752, Cuff made a slightly simplified aquatic microscope for the naturalist, John Ellis, and Ellis included an explanation and illustration of this instrument in his Essay Towards a Natural History of the Corallines (London, 1755), a popular text that was soon republished in French, Dutch and German. Ellis also sent an example of this instrument to Alexander Garden, a physician and naturalist in Charleston, South Carolina, who gave his name to the Gardenia. This was probably the first aquatic microscope, and the first Cuff instrument, in North America.

Cuff may have had many talents, but he was a lousy businessman who went bankrupt in a terribly competitive environment. When George Adams, proprietor of the leading instrument shop in London, offered "Ellis's aquatic microscopes," he essentially erased all memory of the contributions that Cuff and Trembley had made to the form. Most historians have followed Adams' lead, but our aquatic microscope may help restore the record.

Deborah Warner is a Curator of the Physical Sciences Collection in the National Museum of American History. She has also blogged about the buzz for spectroscopy.

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