A pocket barometer/altimeter, unsigned, late nineteenth century, in a leather case, the top of which is missing. It reads from 26 to 31 inches of mercury or 0 to 5000 ft. It is Compensated. The altitude dial can be rotated to set the zero to the pressure reading at the start of a climb - the bezel is milled to facilitate this. Approximately 2 3/4” diameter. The brass case is gilded. The dial is silvered. In good working order although very dirty and tarnished when purchased.