Abstract: A heat actuable directing device suitable for directing a member such as a solar energy collection device to more favored dispositions with respect to the source of heat which actuates the device. The device itself consists of the member to be directed, a fluid container positioned so as to receive more heat from the source of heat when the member to be directed is at a less favorable disposition than it would if at its more favored disposition, a fluid actuable force applying means associated with the member capable of moving the member from a less favored disposition to a more favored disposition with respect to the source of heat and a fluid tight conduit means operatively connecting said fluid container and said fluid actuable force applying means so as to convey fluid pressure increases from the container to the force applying means to thus move said member to be directed to said more favored disposition whenever necessary.