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[1] A simple, so-called "lateral" harmonograph uses two pendulums to control the movement of a pen relative to a drawing surface. One pendulum moves the pen back and forth along one axis, and the other pendulum moves the drawing surface back and forth along a perpendicular axis.
By 1900, two primary types of mimeographs had come into use: a single-drum machine and a dual-drum machine. The single-drum machine used a single drum for ink transfer to the stencil, and the dual-drum machine used two drums and silk-screens to transfer the ink to the stencils. The single drum (example Roneo) machine could be easily used for ...
This second phase brought to mass markets technologies like the small electric motors and the products of industrial chemistry without which the duplicating machines would not have been economical. By bringing greatly increased quantities of paperwork to daily life, the duplicating machine and the typewriter gradually changed the forms of the ...
The cyclostyle was a more automated type of mimeograph machine that produced reproductions faster. In 1893 Francis Galton described a system for sending line drawings through the widely established telegraph system, using simple numeric codes, and printing out the line drawings at the other end from the codes.
2,6-di-tert-butylphenol is a precursor to more complex compounds used as antioxidants and light-protection agents for the stabilization for polymers. Of particular note is methyl-3-(3,5-di- tert -butyl-4-hydroxyphenyl)-propionate (CAS# 6386-38-5), which is formed by the Michael addition of methyl acrylate .
In organic chemistry, phenols, sometimes called phenolics, are a class of chemical compounds consisting of one or more hydroxyl groups (−O H) bonded directly to an aromatic hydrocarbon group. [1] The simplest is phenol, C 6 H 5 OH. Phenolic compounds are classified as simple phenols or polyphenols based on the number of phenol units in the ...
Desmond Paul Henry (1921–2004) was a Manchester University Lecturer and Reader in Philosophy (1949–82). He was one of the first British artists to experiment with machine-generated visual effects at the time of the emerging global computer art movement of the 1960s (The Cambridge Encyclopaedia 1990 p. 289; Levy 2006 pp. 178–180).
At 16 frames per foot, this meant a maximum running time of 20 seconds at 40 frames per second (fps), the speed most frequently employed with the camera. At the rate of 30 fps that had been used on occasion as far back as 1891, a film could run for almost 27 seconds.