Movement 483

483. Dry gas meter. Consists of two bellows-like chambers, A, A', which are alternately filled with gas, and discharged through a valve, B, something like the slide-valve of a steam engine, worked by the chambers, A, A'. The capacity of the chambers being known, and the number of times they are filled being registered by dial-work, the quantity of gas passing through the meter is indicated on the dials.