Pocket Barometer Altimeter by Barker for Casartelli c.1910

A very good lacquered brass aneroid pocket barometer altimeter by Francis Barker for Casartelli & Son, Manchester c.1910. Pocket barometer having 1¾” silvered and die struck dial, outer crown operated altitude scale calibrated in feet with a range from 0 – 10,000ft divided down to 50ft, inner barometric scale calibrated in inches of mercury with a range from 21” – 31” divided down to 1/10th. The upper part marked “Compensated,” the lower signed by the retailer “J. Casartelli & Son, 43 Market St, Manchester.” Blued steel pointer, bevelled glass. The conventional Vidie pattern movement driven from a single 1” nickel alloy capsule and tensioned on a C spring, all contained within a lacquered brass ribbed semi-barrel form case, pendant, bow and crown, calibration port to verso. Presented in its correct round burgundy leather over timber, cream silk and blue velvet case, snap closure on a button release. Condition: The subject of a full service, conservation, and calibration under laboratory conditions. The movement working exceptionally well, see performance chart from dynamic test. Generally very good condition with only minimal signs of handling, some minor marks to dial. The brass case retaining virtually all its original lustrous finish, the leather case structurally sound with light external wear, the cream lid silk with age mark. Comments: An aesthetically attractive instrument in very good condition, a fine example of these rather scarce crown setting altitude barometers. One for the collector and connoisseur alike.