Abstract: The present invention is directed generally toward a modular apparatus for the circulation, filtration, and chlorination of water in an in-ground swimming pool. In more particular, the invention disclosed herein relates to a modular and transportable pool-side unit in which the entire filtration and circulation systems, as well as the lighting and chlorination systems, for the pool are contained. Additionally, the instant invention utilizes a novel traveling main drain, wherein the functions of a conventional pool main drain and an automated pool sweeper are combined. The traveling main drain is moved about the bottom of the pool by the expulsion of water through a single horizontally mounted jet, said jet being free to rotate in a horizontal plane about the central axis of the device and thereby seek another movement direction when the device becomes blocked.

Abstract: Disclosed is an apparatus and method for expanding particulate volcanic ash to produce an expanded substantially monocellular product having a loose bulk density of about 0.5 to about 15 pounds per cubic foot. The apparatus includes an enclosed vessel containing a zone heated to about 930.degree. C. to about 1100.degree. C. by a substantially horizontally projecting flame. The flame may be deviated from horizontal to control the residence time of the ash particles in the heated zone. The pressure in the vessel is maintained at least 10 millimeters of mercury less than atmospheric.

Abstract: Disclosed is a method of making lightweight gypsum products wherein expanded substantially monocellular volcanic ash having a loose bulk density of about 0.05 to about 15 pounds per cubic foot is added to calcined gypsum and water to form a slurry. The hydrated gypsum product formed has a bulk density of about 24 to about 45 pounds per cubic foot.