|
Milwaukee Pierhead Light
The Milwaukee Pierhead Light is an active lighthouse located in the Milwaukee, Wisconsin, Milwaukee harbor, just south of downtown. This aid to navigation is a 'sister' of the Kenosha North Pier Light. History The station was established in 1872. It is west of the Milwaukee Breakwater Light, and is near the outflow of the Milwaukee River—not far east of where that river converged with the Kinnickinnic River (Milwaukee River), Kinnickinnic River—into the Milwaukee Harbor and Lake Michigan. This light has a round steel tower with a round Balcony, gallery and a ten-sided lantern. In 1926, the original 4th Order Fresnel lens was transferred to the Milwaukee Breakwater Light, and that lens is now displayed at the Wisconsin Maritime Museum in Manitowoc, Wisconsin. The Fifth Order Fresnel lens—installed in 1926—was removed in 2005. The tower is newly painted circa 2007. The 5th Order lens is said to be on display also at the Wisconsin Maritime Museum.National Park Service]Mariti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frustum
In geometry, a (from the Latin for "morsel"; plural: ''frusta'' or ''frustums'') is the portion of a solid (normally a pyramid or a cone) that lies between two parallel planes cutting this solid. In the case of a pyramid, the base faces are polygonal, the side faces are trapezoidal. A right frustum is a right pyramid or a right cone truncated perpendicularly to its axis; otherwise it is an oblique frustum. If all its edges are forced to become of the same length, then a frustum becomes a prism (possibly oblique or/and with irregular bases). In computer graphics, the viewing frustum is the three-dimensional region which is visible on the screen. It is formed by a clipped pyramid; in particular, ''frustum culling'' is a method of hidden surface determination. In the aerospace industry, a frustum is the fairing between two stages of a multistage rocket (such as the Saturn V), which is shaped like a truncated cone. Elements, special cases, and related concepts A frustu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
