A bourdon gauge is a type of pressure gauge that measures pressure using a curved tube, typically made of brass. The tube is sealed at one end and attached to a pressure source at the other. When pressure is applied to the gauge, the curved tube tends to straighten out, which causes a pointer attached to the end of the tube to move and indicate the pressure on a dial. Bourdon gauges are commonly used in industrial and mechanical applications, such as in the measurement of fluid pressure in pipelines and boilers