Mcleod Gauges are appropriate for quantity of pressure in the series of 10 mm to 10-² mm or 10-³ mm of Hg. This appropriate gauge is an alteration of Macleod Gauge. This device eradicates the use of a transportable reservoir of mercury, and also necessitates approximately 12 cc of mercury for filling. The total extent of this gauge is approx. 9” X 6”.