Abstract: A multidirectional amphibious safety vehicle comprises an outer cylindrical shell having two opposite ends and a longitudinal axis therethrough; a stationary central pipe having two opposite ends and extending along the longitudinal axis of the outer cylindrical shell; elements, secured around the central pipe, for rotating the outer cylindrical shell about the central pipe whereby the safety vehicle moves forward and backward over land, water, and other terrain; and a motor, mounted on at least one of the two opposite ends of the central pipe, for driving the safety vehicle sideways on water.

Abstract: A recuperative heating system has a heat conductive chimney flue; a fuel combustion chamber exhausting hot waste gases and smoke upwardly through the flue; coaxial ducts about the flue, defining a fresh air flow path downwardly from a cool air intake along the outer duct and upwardly along the inner duct into direct heat exchange relationship with the outer surface of the flue and exhausting outwardly from the inner duct into a warm air room vent; and a plurality of U-shaped conduit tubes, each having its bight within the flue. The legs of each U-shaped tube are of different lengths with the inlet end on the longer leg opening into the outer duct and the outlet end on the shorter leg opening into the inner duct.