What does a aneroid barometer look like?

Aneroid barometers usually look like a clock. A compact round cylinder with a glass front and a dial with pointer.

Unlike mercurial barometers there is no need for a long case.

Aneroid types use a small, collapsible, sealed metal can, to detect changes in pressure. The minute deformity of the can, is amplified by levers to turn the dial. all this can be held in a small instrument case, the size of a wall clock.