Abstract: The present invention relates to a Stirling engine which includes a first wall member forming a part of a vessel, a second wall member forming a part of the vessel, a third wall member forming a part of the vessel which is transformable and at the same time the transformation of which can change the positional relationship of the second wall member relative to the first wall member, a working fluid sealed in the vessel, a heater for heating the working fluid in the vessel through the first wall member, a cooler for cooling the working fluid in the vessel through the second wall member, a regenerator and a mechanical device which is driven by the working fluid when the working fluid is moved relative to the second wall member to change the pressure so that a part of the heat generated by the heater and transferred to the working fluid is used for driving the mechanical device.

Abstract: Improvement in a method for producing electrorecording paper consisting of an electroconductive material of cuprous iodide, a heat sensitive color forming material and a support and forming color in response to an electric signal when current is caused to flow, which comprises adding a reducing agent to a suspension of cuprous iodide to increase resistance of cuprous iodide and to whiten the ground color.