The magic lantern, also known by its Latin name laterna magica, is an early type of image projector that used pictures—paintings, prints, or photographs—on transparent plates, one or more lenses, and a light source. Because a single lens inverts an image projected through it, slides were inserted upside down in the magic lantern, rendering the projected image correctly oriented.
A zoetrope is one of several pre-film animation devices that produce the illusion of motion by displaying a sequence of drawings or photographs showing progressive phases of that motion. It was basically a cylindrical variation of the phénakisticope, suggested almost immediately after the stroboscopic discs were introduced in 1833. The definitive version, with easily replaceable picture strips, was introduced as a toy by Milton Bradley in 1866 and became very successful.
A Fresnel lens is a type of composite compact lens which reduces the amount of material required compared to a conventional lens by dividing the lens into a set of concentric annular sections.
A mirror galvanometer is an ammeter that indicates it has sensed an electric current by deflecting a light beam with a mirror. The beam of light projected on a scale acts as a long massless pointer. In 1826, Johann Christian Poggendorff developed the mirror galvanometer for detecting electric currents. The apparatus is also known as a spot galvanometer after the spot of light produced in some models.
Jean Bernard Léon Foucault was a French physicist best known for his demonstration of the Foucault pendulum, a device demonstrating the effect of Earth's rotation. He also made an early measurement of the speed of light, discovered eddy currents, and is credited with naming the gyroscope.
The Kola Superdeep BoreholeSG-3 is the result of a scientific drilling project of the Soviet Union in the Pechengsky District, near the Russian border with Norway, on the Kola Peninsula. The project attempted to drill as deep as possible into the Earth's crust.
Reflection is the change in direction of a wavefront at an interface between two different media so that the wavefront returns into the medium from which it originated. Common examples include the reflection of light, sound and water waves. The law of reflection says that for specular reflection the angle at which the wave is incident on the surface equals the angle at which it is reflected.
An optical filter is a device that selectively transmits light of different wavelengths, usually implemented as a glass plane or plastic device in the optical path, which are either dyed in the bulk or have interference coatings. The optical properties of filters are completely described by their frequency response, which specifies how the magnitude and phase of each frequency component of an incoming signal is modified by the filter.
A stroboscope, also known as a strobe, is an instrument used to make a cyclically moving object appear to be slow-moving, or stationary. It consists of either a rotating disk with slots or holes or a lamp such as a flashtube which produces brief repetitive flashes of light. Usually, the rate of the stroboscope is adjustable to different frequencies. When a rotating or vibrating object is observed with the stroboscope at its vibration frequency, it appears stationary. Thus stroboscopes are also used to measure frequency.
Well logging, also known as borehole logging is the practice of making a detailed record of the geologic formations penetrated by a borehole. The log may be based either on visual inspection of samples brought to the surface or on physical measurements made by instruments lowered into the hole. Some types of geophysical well logs can be done during any phase of a well's history: drilling, completing, producing, or abandoning. Well logging is performed in boreholes drilled for the oil and gas, groundwater, mineral and geothermal exploration, as well as part of environmental and geotechnical studies.
A single-wire transmission line is a method of transmitting electrical power or signals using only a single electrical conductor. This is in contrast to the usual use of a pair of wires providing a complete circuit, or an electrical cable likewise containing two conductors for that purpose.
Precursors of film are concepts and devices that have much in common with the later art and techniques of cinema.
A projector or image projector is an optical device that projects an image onto a surface, commonly a projection screen. Most projectors create an image by shining a light through a small transparent lens, but some newer types of projectors can project the image directly, by using lasers. A virtual retinal display, or retinal projector, is a projector that projects an image directly on the retina instead of using an external projection screen.
The World Wireless System was a turn of the 20th century proposed telecommunications and electrical power delivery system designed by inventor Nikola Tesla based on his theories of using Earth and its atmosphere as electrical conductors. He claimed this system would allow for "the transmission of electric energy without wires" on a global scale as well as point-to-point wireless telecommunications and broadcasting. He made public statements citing two related methods to accomplish this from the mid-1890s on. By the end of 1900 he had convinced banker J. P. Morgan to finance construction of a wireless station based on his ideas intended to transmit messages across the Atlantic to England and to ships at sea. His decision to change the design to include wireless power transmission to better compete with Guglielmo Marconi's new radio based telegraph system was met with Morgan's refusal to fund the changes. The project was abandoned in 1906, never to become operational.
The experiments of Rayleigh and Brace were aimed to show whether length contraction leads to birefringence or not. They were some of the first optical experiments measuring the relative motion of Earth and the luminiferous aether which were sufficiently precise to detect magnitudes of second order to v/c. The results were negative, which was of great importance for the development of the Lorentz transformation and consequently of the theory of relativity. See also Tests of special relativity.
St Catherine's Lighthouse is a lighthouse located at St Catherine's Point at the southern tip of the Isle of Wight. It is one of the oldest lighthouse locations in Great Britain.
Kosmos 122, launched on 25 June 1966, Meteor No.5L, and was one of eleven weather satellites put into orbit between 1964 and 1969.
Kosmos 144, was launched on 28 February 1967, Meteor No.6L, and was one of eleven weather satellites launched by the Soviet Union between 1964 and 1969. Kosmos 144 was the second announced Russian meteorological satellite and the first interim operational weather satellite in the experimental Kosmos satellite 'Meteor' system. It was also the first launch of the semi-operational weather satellite from the Plesetsk site into a near-polar, near-circular orbit. Unlike U.S. weather satellites, however, the orbit was prograde because, as a result of geographic limitations, a retrograde orbit was not possible. Kosmos 144 was orbited to test, in a semi-operational mode, meteorological instruments designed for obtaining images of cloud cover, snow cover, and ice fields on the day and night sides of the Earth and for measuring fluxes of outgoing radiation reflected and radiated by the Earth-atmosphere system. The launch of the Kosmos 144 satellite occurred after the success of the Kosmos 122 another meteorological satellite that was launched on 25 June 1966. These satellites were used until 1969 when they were replaced with an upgraded model officially called Meteor 1. The Kosmos 144 differed from the Kosmos 122 mission from Baikonur Cosmodrome to Plesetsk Cosmodrome that was used to get the satellite at the inclination that the satellite was left. The Kosmos 144 was also soon joined by the Kosmos 156, on 27 April 1967, which due to the orbit at which the satellites were positioned made it to where one of the satellites would pass over every six hours.
Kosmos 156 was a Soviet weather satellite launched on 27 April 1967, one of eleven weather satellites launched by the Soviet Union between 1964 and 1969. It formed part of the experimental "Meteor" weather satellite system. In 1969, the Kosmos satellite series was scrapped for the more modern and updated Meteor satellite.
