Editing Barometer (section)

==== Barographs ====

{{Main article|Barograph}}

[[File:Barograph 01.jpg|thumb|Analogue recording [[barograph]] using five stacked aneroid barometer cells]]A barograph is a recording aneroid barometer where the changes in atmospheric pressure are recorded on a paper chart.

The principle of the barograph is same as that of the aneroid barometer. Whereas the barometer displays the pressure on a dial, the barograph uses the small movements of the box to transmit by a system of levers to a recording arm that has at its extreme end either a scribe or a pen. A scribe records on smoked foil while a pen records on paper using ink, held in a nib. The recording material is mounted on a cylindrical drum which is rotated slowly by a clock. Commonly, the drum makes one revolution per day, per week, or per month, and the rotation rate can often be selected by the user.