Description
● Used to measure the ambient or atmospheric pressure. It works on the principle of a column of mercury supported by the atmospheric pressure acting on the surface of the mercury reservoir.
● Comprises of a stout glass tube of approx. 5mm bore enclosed in a brass tube.
● A brass engraved dual vernier scale – one reading 25ʺ to 32ʺ and the other from 64cm to 81cm is actuated by a knob by a rack and pinion arrangement.
● A glass cistern at the bottom has an ivory pointer with an adjustment screw that provides a fiducial setting point to which the level of the mercury is adjusted before noting the readings.
● A white reflecting surface behind the scale facilitates easy reading.
● The apparatus is mounted on a wooden board.
(Supplied without mercury)
