The Heidbrink meter in Boyle&;s machine: (A) Reduces pressure of gases, (B) Indicates flow of gases, (C) Indicates humidity of gases, (D) It a fixed orifice meter
Answer is B. Heidbrink is a flowmeter used in past. It consists of a metal tapered tube with inveed black float. The upper-end projects in the glass tube. Other type of flowmeter used in past was Connell which has round bobin.