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Trevose Head Lighthouse
Trevose Head Lighthouse is a lighthouse on Trevose Head on the north Cornish coast at lying to the WSW of Padstow and was sited here as there was previously no light from Land's End to Lundy and it would be visible from Cape Cornwall to Hartland Point. The tower is tall, and has a range of , but, on a clear night, you can just spot the light from Pendeen Lighthouse, over away. History Construction The site was surveyed by order of the Trinity Board in July 1844 with a design submitted that November and approved February 1845. Building began in that May with the laying out of the road and contract entered into with the builders the next month. During gales on 20–21 November 1846 scaffolding attached to the tower was blown away. After completion of the first tower, it was determined that the light was under certain circumstances liable to be mistaken by mariners. A second lower light was therefore proposed and (the decision having been taken in June 1847) it was co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trevose Head
Trevose Head ( kw, Penn Trenfos, meaning ''farm of the wall's headland'') () is a headland on the Atlantic coast of north Cornwall, United Kingdom. It is situated approximately west of Padstow. The South West Coast Path runs around the whole promontory and is within the Cornwall Area of Outstanding Natural Beauty and the Trevose Head Heritage Coast. In clear weather, visitors to Trevose Head can see virtually the whole length of the north Cornwall coast; to the north, the view extends beyond the Cornwall county boundary to Hartland Point (), Devon; to the south, it extends beyond St Ives to the headland at Pendeen Watch (). History The ruins of St Constantine's chapel can be visited at hole 3 of Trevose Golf Club along an ancient right of way. The club is situated between Constantine Bay and Mother Ivey's Bay, behind Booby's Bay. Trevose Head Lighthouse, maintained by Trinity House, is on the north-west corner of the headland and the Padstow lifeboat is stationed on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fresnel Lens
A Fresnel lens ( ; ; or ) is a type of composite compact lens developed by the French physicist Augustin-Jean Fresnel (1788–1827) for use in lighthouses. It has been called "the invention that saved a million ships." The design allows the construction of lenses of large aperture and short focal length without the mass and volume of material that would be required by a lens of conventional design. A Fresnel lens can be made much thinner than a comparable conventional lens, in some cases taking the form of a flat sheet. The simpler dioptric (purely refractive) form of the lens was first proposed by Count Buffon and independently reinvented by Fresnel. The '' catadioptric'' form of the lens, entirely invented by Fresnel, has outer elements that use total internal reflection as well as refraction; it can capture more oblique light from a light source and add it to the beam of a lighthouse, making the light visible from greater distances. Description The Fresnel len ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Air Compressor
An air compressor is a pneumatic device that converts power (using an electric motor, diesel or gasoline engine, etc.) into potential energy stored in pressurized air (i.e., compressed air). By one of several methods, an air compressor forces more and more air into a storage tank, increasing the pressure. When the tank's pressure reaches its engineered upper limit, the air compressor shuts off. The compressed air, then, is held in the tank until called into use. The kinetic energy provided by the compressed air can be used for a variety of applications such as pneumatic tool as it is released air and the tank depressurizes. When tank pressure reaches its lower limit, the air compressor turns on again and re-pressurizes the tank. An air compressor must be differentiated from a pump because it works for any gas/air, while pumps work on a liquid. Classification Compressors may be classified according to the pressure delivered: # Low-pressure air compressors (LPACs), which have ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hornsby-Akroyd Oil Engine
The Hornsby-Akroyd oil engine, named after its inventor Herbert Akroyd Stuart and the manufacturer Richard Hornsby & Sons, was the first successful design of an internal combustion engine using heavy oil as a fuel. It was the first to use a separate vapourising combustion chamber and is the forerunner of all hot-bulb engines, which are considered predecessors of the similar Diesel engine, developed a few years later. Early internal combustion engines were quite successful running on gaseous and light petroleum fuels. However, due to the dangerous nature of petroleum and light petroleum fuel, legal restrictions were placed on their transportation and storage. Heavier petroleum fuels, such as kerosene, were quite prevalent, as they were used for lighting, but posed specific problems when used in internal combustion engines: Oil used for engine fuel must be turned to a vapour state and remain in that state during compression. Furthermore, the combustion of the fuel must be powerf ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acoustician
Acoustics is a branch of physics that deals with the study of mechanical waves in gases, liquids, and solids including topics such as vibration, sound, ultrasound and infrasound. A scientist who works in the field of acoustics is an acoustician while someone working in the field of acoustics technology may be called an acoustical engineer. The application of acoustics is present in almost all aspects of modern society with the most obvious being the audio and noise control industries. Hearing is one of the most crucial means of survival in the animal world and speech is one of the most distinctive characteristics of human development and culture. Accordingly, the science of acoustics spreads across many facets of human society—music, medicine, architecture, industrial production, warfare and more. Likewise, animal species such as songbirds and frogs use sound and hearing as a key element of mating rituals or for marking territories. Art, craft, science and technology have prov ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lord Rayleigh
John William Strutt, 3rd Baron Rayleigh, (; 12 November 1842 – 30 June 1919) was an English mathematician and physicist who made extensive contributions to science. He spent all of his academic career at the University of Cambridge. Among many honors, he received the 1904 Nobel Prize in Physics "for his investigations of the densities of the most important gases and for his discovery of argon in connection with these studies." He served as president of the Royal Society from 1905 to 1908 and as chancellor of the University of Cambridge from 1908 to 1919. Rayleigh provided the first theoretical treatment of the elastic scattering of light by particles much smaller than the light's wavelength, a phenomenon now known as " Rayleigh scattering", which notably explains why the sky is blue. He studied and described transverse surface waves in solids, now known as " Rayleigh waves". He contributed extensively to fluid dynamics, with concepts such as the Rayleigh number (a dimen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acoustic Horn
An acoustic horn or waveguide is a tapered sound guide designed to provide an acoustic impedance match between a sound source and free air. This has the effect of maximizing the efficiency with which sound waves from the particular source are transferred to the air. Conversely, a horn can be used at the receiving end to optimize the transfer of sound from the air to a receiver. Acoustic horns are found in nature in the form of the burrows constructed by male mole crickets to amplify their song. The earliest appearance of the horn in connection to sound in The Times was published in 1786: Applications Acoustic horns are used in: * horn loudspeakers * brass instrument, brass and woodwind musical instruments * vehicle horns such as those used on cars, trucks, train horn, trains, boats, and bicycles * megaphones, often used by lifeguards at public swimming pools. * foghorns, used to warn ships * Ear trumpet, ear horns, used by people who are hard of hearing (the human ear itself h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Siren (alarm)
A siren is a loud noise-making device. Civil defense sirens are mounted in fixed locations and used to warn of natural disasters or attacks. Sirens are used on emergency service vehicles such as ambulances, police cars, and fire engines. There are two general types: mechanical and electronic. Many fire sirens (used for calling the volunteer fire fighters) serve double duty as tornado or civil defense sirens, alerting an entire community of impending danger. Most fire sirens are either mounted on the roof of a fire station or on a pole next to the fire station. Fire sirens can also be mounted on or near government buildings, on tall structures such as water towers, as well as in systems where several sirens are distributed around a town for better sound coverage. Most fire sirens are single tone and mechanically driven by electric motors with a rotor attached to the shaft. Some newer sirens are electronically driven speakers. Fire sirens are often called "fire whistles", " ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fog Signal
A foghorn or fog signal is a device that uses sound to warn vehicles of navigational hazards such as rocky coastlines, or boats of the presence of other vessels, in foggy conditions. The term is most often used in relation to marine transport. When visual navigation aids such as lighthouses are obscured, foghorns provide an audible warning of rock outcrops, shoals, headlands, or other dangers to shipping. Description All foghorns use a vibrating column of air to create an audible tone, but the method of setting up this vibration differs. Some horns, such as the Daboll trumpet, used vibrating plates or metal reeds, a similar principle to a modern electric car horn. Others used air forced through holes in a rotating cylinder or disk, in the same manner as a siren. Semi-automatic operation of foghorns was achieved by using a clockwork mechanism (or "coder") to sequentially open the valves admitting air to the horns; each horn was given its own timing characteristics to help mar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lighthouse At Trevose Head - Geograph
A lighthouse is a tower, building, or other type of physical structure designed to emit light from a system of lamps and lenses and to serve as a beacon for navigational aid, for maritime pilots at sea or on inland waterways. Lighthouses mark dangerous coastlines, hazardous shoals, reefs, rocks, and safe entries to harbors; they also assist in aerial navigation. Once widely used, the number of operational lighthouses has declined due to the expense of maintenance and has become uneconomical since the advent of much cheaper, more sophisticated and effective electronic navigational systems. History Ancient lighthouses Before the development of clearly defined ports, mariners were guided by fires built on hilltops. Since elevating the fire would improve the visibility, placing the fire on a platform became a practice that led to the development of the lighthouse. In antiquity, the lighthouse functioned more as an entrance marker to ports than as a warning signal for reefs an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Light Characteristic
A light characteristic is all of the properties that make a particular navigational light identifiable. Graphical and textual descriptions of navigational light sequences and colours are displayed on nautical charts and in Light Lists with the chart symbol for a lighthouse, lightvessel, buoy or sea mark with a light on it. Different lights use different colours, frequencies and light patterns, so mariners can identify which light they are seeing. Abbreviations While light characteristics can be described in prose, e.g. "Flashing white every three seconds", lists of lights and navigation chart annotations use abbreviations. The abbreviation notation is slightly different from one light list to another, with dots added or removed, but it usually follows a pattern similar to the following (see the chart to the right for examples). * An abbreviation of the type of light, e.g. "Fl." for flashing, "F." for fixed. * The color of the light, e.g. "W" for white, "G" for green, "R" for re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
James Nicholas Douglass
Sir James Nicholas Douglass, (16 October 1826 – 19 June 1898) was an English civil engineer, a prolific lighthouse builder and designer, most famous for the design and construction of the fourth Eddystone Lighthouse, for which he was knighted. Biography James Nicholas Douglass was born in Bow, London, in 1826, the eldest son of Nicholas Douglass, also a civil engineer. After serving an apprenticeship with the Hunter and English company, he joined the engineering department of Trinity House, the United Kingdom's lighthouse authority. Along with his brother William, James worked as an assistant to his father during the construction of James Walker's Bishop Rock Lighthouse in the Scilly Isles, earning the nickname 'Cap'n Jim' during the process.Palmer, M. ''Eddystone: the finger of light'', Seafarer, 2005, , p.103 After a brief period working for the Newcastle carriage builders R J & R Laycock, he returned in 1854 to assist in the lighthouse's final completion and to marr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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