How common are banjo barometers on Sellingantiques?

Around 48 are listed in a year, and 49 different dealers have handled one. It is a form almost any general dealer carries at some point rather than a specialist's preserve. The archive behind this guide runs to 370 listings, sold and for sale.

What period do most of them come from?

The dated field runs from 1800 to 1930. Of the 227 listings with a clean year, 62 fall in the 1880s and 68 in the 1890s, so two-thirds of them sit in that twenty-year stretch. After that come the 1900s with 39, then the 1860s and 1870s. Eighteenth-century cases are the rarest arrivals, at ten listings, one placed at circa 1785.

Which timber turns up most often?

Oak, and by a wide margin: 140 of 370 titles. It is described as carved in 57 and polished in 45, with golden oak named in several. Walnut follows at 44 titles, then mahogany and rosewood, which carry most of the Georgian and inlaid work.

Are mercury or aneroid movements more usual?

Aneroid is named in 20 titles, mercury in 10. The aneroid movement needs no mercury and became the normal fitting for the later Victorian and Edwardian oak cases. Mercury movements and Georgian mahogany cases together account for almost everything at the top of the range.

What does pendant mean in a barometer title?

It describes a small, slim banjo case. Nineteen titles use the word, and those are almost always walnut. Small or smaller qualifies 71 titles in all, so short-format cases are a steady presence rather than an oddity.

Does anything unusual show up in this category?

Now and then, yes. A tortoiseshell case, a black chinoiserie one, an American carved walnut barometer, and a banjo clock-barometer with both dials in the one case. One case is described as oversized, and dial diameters quoted in titles stretch from a 5-inch rosewood example up to a 12-inch wheel barometer.