Barometers Realm

The case is crafted from veneered fine mahogany and reflects the aesthetic of the late Georgian or early Regency period. The unusually elaborate pediment features symmetrical volutes embracing a central carved acanthus leaf — a classical decorative motif rooted in antiquity, symbolizing abundance and permanence, and traditionally associated with elegance and classical architecture. The base of the acanthus element takes the form of a shell-like cartouche, completing the composition in characteristic Regency taste. The lower edge of the pediment is adorned with a carved dentil frieze, a repeating architectural motif originating from the Ionic and Corinthian orders, where it served as a decorative highlight beneath the cornice.

The base of the case includes a rounded recess for the mercury reservoir, covered by a flat mahogany cap. The structure of the niche suggests that the instrument was originally fitted with a boxwood cistern tube with a leather base and equipped with a screw-based transport adjustment system. As is often the case, few mercury barometers survive two centuries with their original tubes intact — and provenance indicates that this particular example left London, its place of manufacture, and resided in the United States for a considerable time before being relocated to the Netherlands in the 20th century. It is currently fitted with a bottle tube: a refined siphon-type mercury tube with a short bend terminating in a pear-shaped reservoir featuring a small opening for atmospheric communication. Such tubes were widely used in continental Europe from around 1690 onward. This replacement tube has excellent vacuum integrity and has been properly adjusted in height to allow for reliable calibration and accurate readings on the scale.

The barometric scale is engraved in London inches of mercury, ranging from 27 to 31, and is equipped with a vernier on a rack-and-pinion mechanism, operated by a wooden knob mounted on the barometer case. The scale is engraved on the right register plate, while the left plate bears three engraved weather terms: Fair, Change, and Rain. The words Fair and Rain are executed in a bold, ornamental style characteristic of early Victorian signage, posters, and type specimens from 1820–1860 — closely resembling typefaces found in specimen books such as those by George Bruce’s Son & Co. and Figgins. These letters feature high contrast strokes, thickened serifs, and flaring terminal shapes resembling tusks or claws. Thin parallel hatching to the right and bottom edges of the letters creates a shaded relief effect, typical of 19th-century engraving. The word Change is engraved in a Gothic script style, with angular verticals and fractured shapes resembling Old English calligraphy. This style, widespread in books from the 15th to 18th centuries, was later revived during the Romantic and Gothic Revivals of the 19th century. Its use here evokes a sense of antiquity, gravity, and transformation — a fitting choice for the term Change.

The register plates are made of thick silvered brass, mounted at a slight inward angle toward each other. A rare feature is the presence of engraver signatures on the reverse of each plate: delicately scratched “Frankhams London 1812”, barely legible. This signature refers to Richard and Henry Frankham, who operated a joint engraving workshop at 12 Wilson Street, Gray’s Inn Road, London. They were officially registered as engravers specializing in scientific instrument dials and scales. On the front of the left plate, a discreet “Cary” inscription is engraved in cursive, identifying the barometer’s maker.

The plates are protected by a thick, flat, optically neutral glass (low-iron glass) with a subtle grey-violet edge. This type of glass was commonly used in precision instruments, display cases, laboratory equipment, and navigational devices due to its high clarity and absence of color distortion. However, it is not possible to determine with certainty whether this is the original glazing.

Mounted on the front of the case is a mercury thermometer housed in a long wooden frame with a flat glass cover. The thermometer can be quickly removed in its entirety by sliding a small brass latch located just below. It features dual Réaumur and Fahrenheit scales, finely engraved on a silvered brass plate and supplemented with text-based thermal indications.

This barometer exemplifies the synthesis of Regency-era elegance with the scientific rigor of early 19th-century British craftsmanship. With its richly detailed carving, engraved plates signed by notable London artisans, and technical sophistication, it stands as a significant artifact within the Cary legacy and the wider tradition of precision meteorological instruments.

London Engravers Frankham

The engravers named Frankham were London-based craftsmen active during the first half of the 19th century, specializing in the engraving of scales and components for scientific instruments. Historical records indicate that two engravers bearing the Frankham surname — Richard Frankham and Henry Frankham — operated in London between approximately 1829 and 1855. They ran a joint workshop at 12 Wilson Street, Gray’s Inn Road (in the Gray’s Inn area) and were officially registered as engravers. In the 1843 edition of the London directory, they are listed precisely as “Frankham, Rd. & Henry, engravers” at this address. Their workshop was active during the late Georgian period and throughout the early Victorian era, spanning roughly from the late 1820s to the mid-1850s. In some historical catalogues, they were even classified as barometer makers, although their primary specialization was the engraving and assembly of instrument scales.

The exact founding date of the Frankhams’ workshop is unknown, but evidence suggests it was already in operation by 1829. It is highly likely that Richard and Henry Frankham were related — their names consistently appear together in sources, indicating a family-run business. Their workshop focused on engraving scales and dials for scientific and meteorological instruments — primarily barometers, thermometers, and similar devices. Surviving examples of antique mercury barometers (both stick and wheel types) bear silvered scales engraved with the inscription “Frankham, 12 Wilson St’t, Gray’s Inn Rd, London”, indicating that the Frankhams produced and engraved the scale for those instruments. Interestingly, their names often appear in unusual locations on the instruments, rather than where the principal manufacturer’s name is typically placed. This reflects the fact that the Frankhams functioned as specialist engravers, not as the principal makers. They produced graduated plates, dials, register plates, and other calibrated components that were then incorporated by various scientific instrument manufacturers.

Their work required a high level of skill in fine metal engraving. They most commonly worked on brass plates, which were silvered and then engraved with extremely precise divisions — in inches of mercury, degrees Fahrenheit, and so forth — along with decorative inscriptions. Some sources also mention that the Frankhams may have handled print orders or related technical work, though their enduring reputation lies in their engraving of barometer and meteorological scales. Such a narrow specialization was typical of the time: major instrument manufacturers often outsourced the engraving of scales and panels to skilled external craftsmen. The Frankhams appear to have been among the most respected in this niche.

By the mid-1850s, changes occurred in the operation of the workshop. According to historical records, by 1855, the firm’s name had changed to “Frankham & Wilson”, while still located at Wilson Street. This indicates the arrival of a new partner — Robert Henry Capel Wilson, whose name appears in official notices from the 1860s as a member of the firm. It is likely that one of the Frankham brothers had either retired or passed away by this time.

The firm Frankham & Wilson continued in the same line of work — producing meteorological components and engraving scales. In fact, in the second half of the 19th century, the firm became known for technical improvements to scientific instruments. According to the Journal of the Society of Arts (16 May 1862), Frankham & Wilson introduced improved pocket aneroid barometers, which drew considerable attention. In a letter dated the same year, explorer David Livingstone specifically requests two of these improved aneroids for his expedition, referencing the journal report. This indicates the high reputation of the firm in the field of meteorological instruments.

In addition, Frankham & Wilson also registered new technical innovations. In 1868, they patented a ceramic scale design (“china slide”) for thermometers — likely referring to a porcelain calibration plate. Thus, the successors to the Frankham workshop not only continued the tradition of precise metal engraving but also contributed to the development of new instrumentation.