Pocket barometer compendium having silvered and engraved barometer dial with calibrations from 21–31 inches of mercury, outer rotating altitude ring from 0-10,000 feet. The upper portion marked “Cartwright & Son,” the lower “Preston” and “Compensated.” Blued-steel pointer, bevelled glass. Drum form case with suspension ring and compensation port, with adjuster at 7 o’clock. 1¼” capsule with early coil spring-tensioned movement, bimetallic compensation.
The verso with compass having mother of pearl Singer’s Patent floating card, with cardinals and intercardinals, transit lock with suspension loop. The circular mercurial thermometer set on a gilt register with calibrations in Fahrenheit having a range from -10 to 160 degrees. The whole presented in a good quality purple velvet and silk-lined brown moroccan leather over wood twin-lidded travel case with button releases.
Presented in very good original condition, the case retaining virtually all its original gilt lacquered finish, working well with good sensitivity and transition. The compass finds north easily, the transit lock works well, the thermometer reads correctly. The travel case in similarly fine condition.
This instrument is of interest – the movement is almost certainly French and of the early coil spring-tensioned design originating in the 1860s, though the rest of the instrument is clearly later, and the dial would indicate Short & Mason. This may well be a brokered piece, outsourced and built around components from different manufacturers. Cartwright was solely a retailer, not a maker.
These compendia are becoming increasingly difficult to find and must now be considered very scarce in this condition. A well-recommended collector’s piece.
G. Cartwright & Son, opticians, working from Fishergate, Preston, was established in 1820 and continued into the 20th century.
Dimensions: 3″ high x 1½” wide
Stock No: CP0425