Abstract: A machine is employed for recovering heavy metals and precious or semi precious minerals, such as gold, copper, lead, diamonds, and garnets from placer, or hard rock ore. The machine employs a cylindrical, annular outer drum mounted for rotation at an inclination to the horizontal and including at least one spiral vane extending the length of its inner surface. A cylindrical, annular inner barrel is mounted within the drum and has an upper fragmentation section, an intermediate screened section, and a lower discharge section. A spray of water is directed into the inner barrel and a water spray bar is located in the annulus between the inner barrel and the outer drum. A fine sluice box is located to receive under one-quarter material input from a side trommel and a coarse sluice box located to receive discharge from the side trommel and discharge from the fine sluice box. The sluice box includes a plurality of landings, matting and screens upon which heavy materials, such as gold or precious stones, collect.

Abstract: A machine is employed for recovering heavy metals and precious or semi precious minerals, such as gold, copper, lead, diamonds, and garnets from placer, or hard rock ore. The machine employs a cylindrical, annular outer drum mounted for rotation at an inclination to the horizontal and including at least one spiral vane extending the length of its inner surface. A cylindrical, annular inner barrel is mounted within the drum and has an upper fragmentation section, an intermediate screened section, and a lower discharge section. A spray of water is directed into the inner barrel and a water spray bar is located in the annulus between the inner barrel and the outer drum. A fine sluice box is located to receive under one-quarter material input from a side trommel and a coarse sluice box located to receive discharge from the side trommel and discharge from the fine sluice box. The sluice box includes a plurality of landings, matting and screens upon which heavy materials, such as gold or precious stones, collect.

Abstract: A method of heavy particle separation, including a primary separation stage which includes the steps of dropping, accumulating, concentrating and discharging of heavy particles and/or a secondary separation stage for concentrating heavy particles which includes the steps of infeeding, stilling and retaining such particles.

Abstract: The invention relates to an apparatus for and method of automatically actuating the movement of a rudder of a watercraft between a steering and a non-steering position in response to the speed of the watercraft. This invention is particularly applicable for use in jet-propelled watercraft, which have reduced steering capacity at low speeds.

Abstract: An apparatus is provided for reducing the extent of heel of a nautical vessel by applying a buoyant righting moment on the leeward side of a hull of the vessel. Supports are coupled to and extend laterally beneath the hull and carry hollow bulbs on their extremities. The bulbs on both sides of the vessel are each divided by fore and aft partitions into inboard and outboard chambers. A passage is defined between the inboard chambers and a separate passage is defined between the outboard chambers. A first fluid fills the outboard chambers and the passage therebetween, while a second fluid having a specific gravity different than that of the first fluid fills, the inboard, chambers and the passageway therebetween.

Abstract: A machine is employed for recovering heavy metals, such as gold, from placer ore. The machine employs a cylindrical, annular outer drum mounted for rotation at an inclination to the horizontal and including at least one spiral vane extending the length of its inner surface. A cylindrical, annular inner barrel is mounted within the drum and has an upper fragmentation section, an intermediate trommel section, and a lower discharge section. A spray of water is directed into the inner barrel and a water spray bar is located in the annulus between the inner barrel and the outer drum. A sluice box is located to receive an input discharge from the upper end of the outer drum. The ore is separated into large tailings that are discharged from the lower end of the inner barrel and fine, light tailings from the outer drum.