Abstract: An apparatus for sensing the pressure of a well fluid in a subsurface wellbore in which a first, elongated tubing is adapted to extend from the surface of the earth to a subsurface location at which the pressure is to be measured, a fluid receiving chamber is disposed on the lower end of the first tubing, a second, elongated tubing, of smaller cross-section than the first, is disposed in the first tubing with its upper end at the surface of the earth and its lower end sealed within the lower end of the first tubing or the upper end of the fluid receiving chamber and is adapted to receive a pressure transmitting fluid and to be placed in fluid communication with the fluid receiving chamber and a pressure responsive closure element closes the lower end of the first tubing, the upper end of the fluid receiving chamber or the lower end of the fluid receiving chamber and is adapted to open at a pressure above the pressure of the well fluid and permit the pressure of the well fluid to be balanced against the pressu