ENGLISH WHEEL BAROMETER
Barometer, made by Joseph Amadio, c. 1860
The mahogany-veneered onion-top case has an elegant shape. The silvered brass barometer register plate is protected by a convex glass, set in a solid brass bezel. At the top is a hygrometer, in the neck a removable bow-front thermometer and at the bottom a spirit level. At the back there is a long door giving access to a Torricelli tube.
The circular silvered brass register plate is signed by the maker in the following manner:
The atmospheric pressure is indicated by a pierced blued-steel central sweep hand on a scale divided in Imperial inches (28-31) with the corresponding texts for the weather conditions. This hand is connected to a pulley, which is operated by a mercury-filled float on the meniscus level in the mercury tube, counterbalanced by a glass counter weight in an empty tube. The brass setting hand can be moved by turning an ivory knob below the barometer scale. The mercury thermometer has a silvered brass register plate divided in degrees Fahrenheit, whilst the hygrometer indicates the humidity with the words dry and
Joseph Amadio was a successful retailer of microscopes, slides and related equipment, in mid-nineteenth century London. His father, Francis (Francesco), was a well-regarded maker of barometers and thermometers. Both Joseph and his brother, also named Francis, likewise became barometer makers. Joseph later turned to primarily sell microscopes and other optical devices, probably in the mid-1850s. At some point there was a barometer-making partnership of F. Amadio and Son, although which son(s) was involved is not clear. The younger Francis gave up his barometer & thermometer business in the early 1860s, and was taken in by his brother. For a brief period, from about 1863 until Francis’ death in 1866, the microscope business was known as F. & J. Amadio.
Nicholas Goodison, English Barometers 1680-1860, Woodbridge, 1977, p. 297
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