Abstract: A pressure measuring and regulating device and method for measuring and controlling the pressure within an enclosure such as a pressurized cuff of a medical apparatus, e.g. an endotracheal tube, a tracheostomy tube, or the like, includes effecting communication between a chamber in one end of a hollow barrel. Within the bottom of the chamber is disposed a reservoir containing an indicating fluid, such as mercury. The reservoir communicates with an indicating channel which is visible from the exterior of the barrel. The chamber and the reservoir are exposed to the pressures within the enclosure such that the indicating fluid is displaced into the indicating channel to provide an indication of the pressure within the enclosure. An exteriorly operated regulating member is provided for effecting precise adjustment of the chamber pressure and thus the enclosure pressure and which pressure is simultaneously registered in relation to a monitoring scale associated with the indicating channel.