This is a early 1900’s pocket surveying aneroid altimeter barometer signed by Keuffel Esser New York and made by well known British barometer and compass maker Francis Barker and Son (logo of the maker on the back of the case). The silver barometer dial goes from 28-31 in/mercury and the altimeter scale from zero to 3000 feet adjusted by a knob. The calibration is made from an dialing knob. The body of the altimeter is made of brass and is in very good condition. The original case is made of leather and purple velvet and the leather is a bit dry. Some wear and tear present due to the age. Dimensions: 68 mm diameter and 28 mm height.