Abstract: An improved gas-fired cooking device and associated cooking utensils is disclosed. The cooking device includes a hollow cylindrical base member having a closed bottom end. A plurality of legs are secured to the base member, each leg having a lower end adapted to engage a horizontal surface and an upper end extending vertically upwardly above the base member. An annular support ring is secured to each of the legs at the upper end thereof. A cooking vessel is provided having support means attached to the exterior surface thereof for engaging the support rings so as to be supported above the base member. A gas burner assembly is adjustably supported on the bottom end of the base member. The gas burner assembly may be adjusted upwardly or downwardly so as to move it toward or away from the supported cooking vessel. Cooking baskets are also provided for use within the cooking vessel.

Abstract: A heat exchange apparatus which utilizes the solar heat, hot spring water or underground water comprises a cylindrical main body, an internal cylinder placed in the main body, a blower provided in an upper part of the internal cylinder, an air intake, a number of radially arranged air exhaust tubes, ring shaped upper and lower heat exchange compartments, and chambers formed between heat exchange compartments, on and under the upper and lower heat exchange compartment, upper and lower chambers are connected by coil tubes placed in heat exchange compartments, the outer coil tubes and inner coil tubes are successively connected so that each of connected coil tubes has the same overall length, which improves efficiency of heat exchange between air and water which are caused to move in a counterflow fashion.