The Short & Mason barograph mechanism overall is of fine gilded brass construction. Conventional 8-day drum recorder, bearing “Pat. No. 3715.02” to top plate and serial no. “2245” to lower plate, with good quality platform escapement, captive winding key and top cover. The whole mounted on a conical base with static top mounted platform gear, serial no. “2245.” The barometer set on separate, unsigned chassis with fluted border and raised on four turned brass supporting pillars, eight capsule pressure sensing set with adjustment wheel over, having well-engineered connecting mechanism and driving swinging gate arm and indicator to barometric scale. Base-mounted arrester bar with single stop pin. Silvered and engraved brass open-faced 4½” dial with conventional annotation calibrated from 28-31 inches of mercury, bearing registered design no. “428606” and retailer’s name “Lennie, Edinburgh” to bottom. Conventional corked ink bottle with dipper, inset to cabinet base. The whole contained within its original oak case with lift-off cover of heavy bevelled five-glass construction. Frieze drawer to bottom for self-adhesive style charts.

The barograph movement having been professionally dismantled, cleaned and inspected, all pivots and moving parts high-polished and precisely reassembled, a new arm manufactured and fitted to the correct length (most are broken or too short). It is in full working order.

The fine tuning of this barograph means that it is extremely sensitive and outperforms any other that we’ve seen, recording even minute barometric fluctuations. The unusual trace, shown in the photographs of the barograph drum, has been discussed with a meteorologist who confirms that the most likely explanation, as there is no seismic activity in this area, is that the fluctuations are caused by oscillations in air pressure created by wind over terrain (we are based in a valley surrounded by hills). The last trace photograph, taken a few days later during a period of stable pressure, exemplifies the instrument’s sensitivity, still indicating, as it does, minute variations.

Instruments with this combination of barograph and aneroid barometer may be considered scarce. This Short & Mason barograph is particularly unusual in that the case has suffered no sun damage and the mechanism is in such good original condition. It has restored very well.

Dimensions: 14″ wide x 9″ high x 8½” deep

Stock No: BG0277

Price: SOLD