level of 40 90 psig the pressure is maintained within the chamber in the aforesaid range preferably by the use of a pressure regulator on the supply line or conduit 34 or on a vent port not shown while the apparatus is maintained in the vessel 44 the temperature within the oven 50 is elevated to a level of 340 u00b0 f the elevated temperature is maintained for sufficient time such that the adhesive bonding the strain gage to the load cell is completely cured under the force of the fluid pressure acting on the surface of the strain gage it has been found satisfactory in the present practice of the invention to maintain the curing temperature for a period of three 3 hours it will be understood however that other combinations of time and temperature may also be employed depending upon the curing properties of the particular adhesive employed the adhesive applied to the strain gage effects a seal around the edge of the strain gage such that fluid pressure acts on the surface of the gage presses the strain gage against the surface to which it is bonded this pressure results in a thin well dispursed layer of adhesive between the strain gage and the surface of the members to be strained the present invention thus provides a unique and novel technique for utilizing fluid pressure acting directly on the surface of the strain gage to provide the clamping force uniformly distributed over the surface of the strain gage to thereby produce a uniform and strong bond of the strain gage to the member to be strained the present invention thus eliminates the need for special positioning or clamping devices for installing.