Abstract: A buoyancy engine having a wheel, incorporating recesses on its periphery to contain linked buoyant lifting bodies, is attached by arms to a driveshaft and immersed in a vessel of liquid. The driveshaft is rotably mounted on sealed bearings in the vessel walls. The buoyant lifting bodies are linked into a continuous loop by flexible attaching hinges. The lifting bodies are introduced at the base of the wheel through an injection tube. The injection tube contains air injectors, powered by a compressor or blower, and the volume of air injected is controlled by a computer controller programmed with the amount of air required to allow the injection of the lifting bodies into the vessel, without significant loss of liquid from the vessel. When operating, the lifting bodies are injected into the vessel at a point below the wheel, and are held by the recesses on the wheel during their ascent through the liquid.