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Walker Evans photograph of three sharecroppers, Frank Tengle, Bud Fields, and Floyd Burroughs, Alabama, summer 1936. Let Us Now Praise Famous Men grew out of an assignment that Agee and Evans accepted in 1936 to produce a Fortune article on the conditions among sharecropper families in the American South during the Great Depression.
Walker Evans (November 3, 1903 – April 10, 1975) was an American photographer and photojournalist best known for his work for the Resettlement Administration and the Farm Security Administration (FSA) documenting the effects of the Great Depression.
The circle cutter is a basic variation of the beam compass. There are many types of circle cutters. This cutter is used primarily to score a circular pattern in the drywall to fit over recessed lighting in the ceiling. The tool consists of a square shank with a sliding pivot that is locked into the desired location with a turn knob.
Many differential screw configurations are possible. The micrometer adjuster pictured uses a nut sleeve with different inner and outer thread pitches to connect a screw on the adjusting rod end with threads inside the main barrel; as the thimble rotates the nut sleeve, the rod and barrel move relative to each other based on the differential between the threads.
A flat spring fixed only at one end like a cantilever, while the free-hanging end takes the load. Coil spring Also known as a helical spring. A spring (made by winding a wire around a cylinder) is of two types: Tension or extension springs are designed to become longer under load. Their turns (loops) are normally touching in the unloaded ...
The reduction compass or proportional dividers is a geometry tool with asymmetric-length branches to allow performing homothetic transformations, reproducing a pattern while enlarging or reducing its size and conserving angles. It was invented by Fabrizio Mordente before 1567.
The tool's design is based on a dental impactor, [6] a device that taps dental amalgam into cavities in teeth. [4] Activator I was patented by Activator Methods International on September 26, 1978. [4] [7] [8] Activator II was released, with an added "impedance head", in 1994. [4]
Many years later, Evans' invention would be sold off for parts. On July 16, 2005, Philadelphia celebrated the 200th anniversary of Oliver Evans's Orukter Amphibolos. Many historians describe Oliver Evans' invention as the United States' first land and water transporter. [46] 1805 Vapor-compression refrigeration. Schematic of Gorrie's 1841 ice ...