The procedure and characteristic of the arc discharge,feature of ignitron,firing way,structure features and its application are described in the paper.
It includes the function of vacuometer, atmospheric pressure altimeter, thermometer (environment) and pressuremeter (for example the standard pressure meter of sphygmomanometer calibration).
Kind of moisture expellable, smell preventive shoe is characterized by that the whole shoe liner is made into a form of gas pump which can expel the moist air out in the shoe.