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Francis Watkins Microscope
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20024
A Fine & Rare 18th Century Compound Monocular Microscope by Francis Watkins:
English ca. 1754. Made of lacquered brass, steel and glass. The microscope is signed in script F Watkins London on the top of the ocular assembly. It stands 32.5 cm tall when fully assembled. To the top plate is mounted by threaded section, a conical, two element, main optical tube with eyepiece. There is a 7-bead circular objective disc below the top plate which reads the objective number in use (1-7) through a small aperture in the top. Coarse focusing is achieved by stage movement on the rectangular limb to pre-set stops numbered S: 7-3 and D: 7-3. The "S" for use with a single lens, and the "D" for use with a double lens, or as a compound microscope. Fine focusing is by a knurled thumb screw on the lower part of the limb. The fine focus control operates a rod embedded in the limb which travels to the top plate. The microscope stage has a brass compression ring on the top for holding microscope slides and a tensioned brass clip on the bottom for holding glass zoophyte tubes. Connected at the limb’s “L” juncture is a gimbled plano-concave mirror on an articulated steel rod. The entire upper limb assembly is connected to the lower limb assembly by a compass joint with an adjustable wing nut. The lower limb assembly is a decorative brass pillar connected to a removable, splayed tripod base. Present with the microscope is Watkins’ signature brass slide canister holding 7 numbered bone microscope slides, and two brass slides for analysis of small samples. The seven numbered slides have 4 sample apertures each, along with an accompanying list of objects to identify the specimens. The samples are held in place by mica discs and brass retaining rings. All samples are present. One of the brass slides is for preparing small samples and/or pond water. The other is hinged, for the same application, or a variety of other different uses. (See the Watkins illustration from his " L' Exercise du Microscope" below.) Discussion:
Francis Watkins (1723-1791) was an English scientific instrument maker working in London in the early 18th century (4). He started his optical business at 4/5 Charing Cross in 1747 and ran it there until his retirement in 1784. His advertisements refer to his shop sign at “Sir Isaac Newton’s Head,” inferring the availability of various types of mathematical and philosophical instruments. In 1763, he formed a partnership with one of his apprentices, Addison Smith, which mainly sold Watkins like microscopes with Smith’s signature. With his retirement in 1784, he passed his business on to his nephews Walter and Jeremiah. After some time, the business was then passed on to Jeremiah’s son Francis Jr. (1798-1818). Francis Watkins Jr. formed an alliance with the then shop foreman, William Hill, and the business became known as Watkins & Hill (1818-1856). Sadly, each of these partners died during their alliance, and the business was then managed by Francis Watkins Jr.’s widow for some time. The business was eventually sold to Elliott Brothers in 1856.
Francis Watkins microscopes are of a unique and delicate design (1,2,3). They are easily recognized by the introduction of a distinctive “L” shaped hinged joint on the microscope limb. This allowed the instrument to recline, and its position fixed by a simple twist of the winged headed screw. This made the user interface, usually from a seated position, much more ergonomic in its ease of operation. They were also engineered to be portable instruments, and disassemble into a small, fitted case, usually with a fair complement of accessories. Incredibly, a microscope with accessories standing 32.5 cm tall can disassemble and fit into a 14 X 14 X 5 cm partitioned case. The cases were usually of wood covered in black rayskin with two hinges, and two sets of "C" hooks and eye-catches. Condition:
This highly desirable microscope is in excellent overall condition. Both optical elements in the main optical tube are in excellent condition. Not suprisingly, one of the elements is an early acromatic doublet. All 7 beads in the circular objective array are present. The microscope provides clear and erect images of increasing magnification. The higher powers easily resolve the intricate lattice detail present in the eye lens of an Anopheles mosquito.
Bibliography:
1. Turner, Gerard L’E (1989) The Great Age of The Microscope; (The collection of the Royal Microscopical Society through 150 years) ISBN [0-85274-020-4] p. 262-264.
2. Turner, Gerard L’E (1981) Collecting Microscopes ISBN [0-8317-5950 x] p. 94.
3. Henderson, J.E.; et. al. (1987) The Billings Microscope Collection 2nd Ed. ; Item No. AFIP 518893-66-6221; p. 182
4. Clifton, Gloria (1995) Directory of British Scientific Instrument Makers 1550-1851. ISBN [0-302-00634 6]; p. 290.
English ca. 1754. Made of lacquered brass, steel and glass. The microscope is signed in script F Watkins London on the top of the ocular assembly. It stands 32.5 cm tall when fully assembled. To the top plate is mounted by threaded section, a conical, two element, main optical tube with eyepiece. There is a 7-bead circular objective disc below the top plate which reads the objective number in use (1-7) through a small aperture in the top. Coarse focusing is achieved by stage movement on the rectangular limb to pre-set stops numbered S: 7-3 and D: 7-3. The "S" for use with a single lens, and the "D" for use with a double lens, or as a compound microscope. Fine focusing is by a knurled thumb screw on the lower part of the limb. The fine focus control operates a rod embedded in the limb which travels to the top plate. The microscope stage has a brass compression ring on the top for holding microscope slides and a tensioned brass clip on the bottom for holding glass zoophyte tubes. Connected at the limb’s “L” juncture is a gimbled plano-concave mirror on an articulated steel rod. The entire upper limb assembly is connected to the lower limb assembly by a compass joint with an adjustable wing nut. The lower limb assembly is a decorative brass pillar connected to a removable, splayed tripod base. Present with the microscope is Watkins’ signature brass slide canister holding 7 numbered bone microscope slides, and two brass slides for analysis of small samples. The seven numbered slides have 4 sample apertures each, along with an accompanying list of objects to identify the specimens. The samples are held in place by mica discs and brass retaining rings. All samples are present. One of the brass slides is for preparing small samples and/or pond water. The other is hinged, for the same application, or a variety of other different uses. (See the Watkins illustration from his " L' Exercise du Microscope" below.) Discussion:
Francis Watkins (1723-1791) was an English scientific instrument maker working in London in the early 18th century (4). He started his optical business at 4/5 Charing Cross in 1747 and ran it there until his retirement in 1784. His advertisements refer to his shop sign at “Sir Isaac Newton’s Head,” inferring the availability of various types of mathematical and philosophical instruments. In 1763, he formed a partnership with one of his apprentices, Addison Smith, which mainly sold Watkins like microscopes with Smith’s signature. With his retirement in 1784, he passed his business on to his nephews Walter and Jeremiah. After some time, the business was then passed on to Jeremiah’s son Francis Jr. (1798-1818). Francis Watkins Jr. formed an alliance with the then shop foreman, William Hill, and the business became known as Watkins & Hill (1818-1856). Sadly, each of these partners died during their alliance, and the business was then managed by Francis Watkins Jr.’s widow for some time. The business was eventually sold to Elliott Brothers in 1856.
Francis Watkins microscopes are of a unique and delicate design (1,2,3). They are easily recognized by the introduction of a distinctive “L” shaped hinged joint on the microscope limb. This allowed the instrument to recline, and its position fixed by a simple twist of the winged headed screw. This made the user interface, usually from a seated position, much more ergonomic in its ease of operation. They were also engineered to be portable instruments, and disassemble into a small, fitted case, usually with a fair complement of accessories. Incredibly, a microscope with accessories standing 32.5 cm tall can disassemble and fit into a 14 X 14 X 5 cm partitioned case. The cases were usually of wood covered in black rayskin with two hinges, and two sets of "C" hooks and eye-catches. Condition:
This highly desirable microscope is in excellent overall condition. Both optical elements in the main optical tube are in excellent condition. Not suprisingly, one of the elements is an early acromatic doublet. All 7 beads in the circular objective array are present. The microscope provides clear and erect images of increasing magnification. The higher powers easily resolve the intricate lattice detail present in the eye lens of an Anopheles mosquito.
Bibliography:
1. Turner, Gerard L’E (1989) The Great Age of The Microscope; (The collection of the Royal Microscopical Society through 150 years) ISBN [0-85274-020-4] p. 262-264.
2. Turner, Gerard L’E (1981) Collecting Microscopes ISBN [0-8317-5950 x] p. 94.
3. Henderson, J.E.; et. al. (1987) The Billings Microscope Collection 2nd Ed. ; Item No. AFIP 518893-66-6221; p. 182
4. Clifton, Gloria (1995) Directory of British Scientific Instrument Makers 1550-1851. ISBN [0-302-00634 6]; p. 290.
Watkin's illustration of his microscope and accessories
taken from his "L' Exercise du Microscope" 1754
Francis Watkins trade card with signed receipt.
Watkin's illustration of his solar and simple microscopes.
Watkin's rendition of subjects as viewed through his microscopes. "L' Exercise du Microscope" 1754
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