Early microscopes were sold by scientists and craftsmen, but by 1660 their production shifted to more commercial workshops.
Beginning in the 18th century there were craftsmen who specialized in the construction of microscopes. Although some improvements were made on the lens production in the 17th century, the outcome depended much on individual talent. The knowledge on lens production was usually lost because the trade secrets were not passed on.
The first 'simple' microscopes used a single lens, but soon 'compound microscopes' with two lenses where introduced. The magnification power and resolution were similar for the two types, so most developments were in the design and mechanics. Along with the physical shape, the material used to construct the instruments changed as well.
During the 18th century, both types were popular, and each had different advantages. The simple microscope was light and small. The compound microscope offered a longer focal length and a more comfortable working distance but needed a stable stand.
Skilled craftsmen and instrument makers soon developed the “variable microscope”, a microscope where the optical unit (single or compound) could be changed.
These microscopes from our collection show examples of the various shapes and designs from the 18th and early 19th century.
This microscope was made by J. Finlayson in Edinburgh in 1743. The stand is ebony and the optical unit is made from paper maché, brass and ivory. In earlier microscopes, the tube of the optical unit was often made from paper and mounted in the middle of two or three feet.
John Cuff changed microscope design to provide sturdy support and free up access to the specimen stage. There was also an important development with the mechanism for the fine focusing. The design of this “New Constructed Double Microscope” was so popular that it dominated designs of the microscopes for the next 50 to 60 years.
This silver variable microscope was probably made by George Adams and then refurbished by C.W. Dixey, who replaced Adam's name with his own.
The variable microscope was constructed in the workshop of George Adams the Elder (1704-1773) from 1770 until his death in 1773. His son, who continued his business, dropped this design.
Made by Dollond, one of the most prestigious London opticians. This object was probably not used very often, as it doesn’t show signs of use and the accessories are still complete.
The optical unit doesn't include achromatic lenses, even though it was available at the time of production. This object was probably not used very oftenThis suggests this microscope was for recreational study. These microscopes were sold alongside the newer 'corrected' achromatic instruments, which suggests people were as intrigued by mechanical innovation as they were by optical innovation.