Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group on the periodic table, a reactive nonmetal, an oxidizing agent that forms oxides with most elements as well as with other compounds. By mass, oxygen is the third-most abundant element in the universe, after helium. At standard temperature and pressure, two atoms of the element bind to form dioxygen, a colorless and odorless diatomic gas with the formula O2. Diatomic oxygen gas constitutes 20.8% of the Earth's atmosphere. As compounds including oxides, the element makes up half of the Earth's crust. Dioxygen is used in cellular respiration and many major classes of organic molecules in living organisms contain oxygen, such as proteins, nucleic acids and fats, as do the major constituent inorganic compounds of animal shells and bone. Most of the mass of living organisms is oxygen as a component of water, the major constituent of lifeforms. Oxygen is continuously replenished in Earth's atmosphere by photosynthesis, which uses the energy of sunlight to produce oxygen from water and carbon dioxide.
Oxygen is too chemically reactive to remain a free element in air without being continuously replenished by the photosynthetic action of living organisms. Another form of oxygen, ozone absorbs ultraviolet UVB radiation and the high-altitude ozone layer helps protect the biosphere from ultraviolet radiation. However, ozone present at the surface is a byproduct of thus a pollutant. Oxygen was isolated by Michael Sendivogius before 1604, but it is believed that the element was discovered independently by Carl Wilhelm Scheele, in Uppsala, in 1773 or earlier, Joseph Priestley in Wiltshire, in 1774. Priority is given for Priestley because his work was published first. Priestley, called oxygen "dephlogisticated air", did not recognize it as a chemical element; the name oxygen was coined in 1777 by Antoine Lavoisier, who first recognized oxygen as a chemical element and characterized the role it plays in combustion. Common uses of oxygen include production of steel and textiles, brazing and cutting of steels and other metals, rocket propellant, oxygen therapy, life support systems in aircraft, submarines and diving.
One of the first known experiments on the relationship between combustion and air was conducted by the 2nd century BCE Greek writer on mechanics, Philo of Byzantium. In his work Pneumatica, Philo observed that inverting a vessel over a burning candle and surrounding the vessel's neck with water resulted in some water rising into the neck. Philo incorrectly surmised that parts of the air in the vessel were converted into the classical element fire and thus were able to escape through pores in the glass. Many centuries Leonardo da Vinci built on Philo's work by observing that a portion of air is consumed during combustion and respiration. In the late 17th century, Robert Boyle proved. English chemist John Mayow refined this work by showing that fire requires only a part of air that he called spiritus nitroaereus. In one experiment, he found that placing either a mouse or a lit candle in a closed container over water caused the water to rise and replace one-fourteenth of the air's volume before extinguishing the subjects.
From this he surmised that nitroaereus is consumed in both combustion. Mayow observed that antimony increased in weight when heated, inferred that the nitroaereus must have combined with it, he thought that the lungs separate nitroaereus from air and pass it into the blood and that animal heat and muscle movement result from the reaction of nitroaereus with certain substances in the body. Accounts of these and other experiments and ideas were published in 1668 in his work Tractatus duo in the tract "De respiratione". Robert Hooke, Ole Borch, Mikhail Lomonosov, Pierre Bayen all produced oxygen in experiments in the 17th and the 18th century but none of them recognized it as a chemical element; this may have been in part due to the prevalence of the philosophy of combustion and corrosion called the phlogiston theory, the favored explanation of those processes. Established in 1667 by the German alchemist J. J. Becher, modified by the chemist Georg Ernst Stahl by 1731, phlogiston theory stated that all combustible materials were made of two parts.
One part, called phlogiston, was given off when the substance containing it was burned, while the dephlogisticated part was thought to be its true form, or calx. Combustible materials that leave little residue, such as wood or coal, were thought to be made of phlogiston. Air did not play a role in phlogiston theory, nor were any initial quantitative experiments conducted to test the idea. Polish alchemist and physician Michael Sendivogius in his work De Lapide Philosophorum Tractatus duodecim e naturae fonte et manuali experientia depromti described a substance contained in air, referring to it as'cibus vitae', this substance is identical with oxygen. Sendivogius, during his experiments performed between 1598 and 1604, properly recognized that the substance is equivalent to the gaseous byproduct released by the thermal decomposition of potassium nitrate. In Bugaj’s view, the isolation of oxygen and the proper association of the substance to that part of air, required for life, lends sufficient weight to the discovery of oxygen by Sendivogius.
Atlantic 75-class lifeboat
The Atlantic 75 is part of the B-Class of lifeboats that serve the shores of the United Kingdom as a part of the RNLI inshore fleet. The Atlantic 75 is the second generation Rigid Inflatable Boat in the B-class series, developed from the Atlantic 21; these boats replaced the Atlantic 21 fleet, but have now been superseded by the new Atlantic 85 lifeboat. One of the main improvements made to the Atlantic 75 is the addition of a ballast tank at the front of the boat which enables the boat to launch into larger surf than the Atlantic 21; the ballast when full, either of sea water or water from a hose, weighs the same as three grown men. RNLI Fleet: B-class Atlantic 75 class lifeboat at Burnham-on-Crouch RNLI Lifeboat Station
Electronic Chart Display and Information System
An Electronic Chart Display and Information System is a geographic information system used for nautical navigation that complies with International Maritime Organization regulations as an alternative to paper nautical charts. IMO refers to similar systems not meeting the regulations as Electronic Chart Systems. An ECDIS system displays the information from Electronic Navigational Charts or Digital Nautical Charts and integrates position information from position and speed through water reference systems and optionally other navigational sensors. Other sensors which could interface with an ECDIS are radar, Automatic Identification Systems, depth sounders. In recent years concerns from the industry have been raised as to the system's security with regards to cyber attacks and GPS spoofing attacks. ECDIS provides navigational safety information; the system generates audible and/or visual alarms when the vessel is in proximity to navigational hazards. The two most used types of electronic chart data are listed below.
ENCs are vector charts that conform to the requirements for the chart databases for ECDIS, with standardized content and format, issued for use with ECDIS on the authority of government authorized hydrographic offices. ENCs are vector charts that conform to International Hydrographic Organization specifications stated in IHO Publication S-57. ENCs contain all the chart information necessary for safe navigation, may contain supplementary information in addition to that contained in the paper chart. Systems using ENC charts can be programmed to give warning of impending danger in relation to the vessel's position and movement. ECDIS systems must be certified according to IMO regulations. Raster Navigational Charts are raster graphics charts that conform to IHOS-61 and are produced by converting paper charts to digital image by scanner; the image is similar to digital camera pictures, which could be zoomed in for more detailed information as it does in ENCs. IMO Resolution MSC.86 permits ECDIS equipment to operate in a Raster Chart Display System mode in the absence of ENC.
ECDIS is an approved marine navigational chart and information system, accepted as complying with the conventional paper charts required by Regulation V/19 of the 1974 IMO SOLAS Convention. As amended; the performance requirements for ECDIS are defined by IMO and the consequent test standards have been developed by the International Electrotechnical Commission in International Standard IEC 61174. In the future, the ENC will be part of a product specification family, based on the "IHO Universal Hydrographic Data Model", known as S-100; the product specification number S-101 has been assigned to the ENC. Nautical chart e-Navigation concept IMO Hydro International – news about hydrography, marine mapping and electronic charting Fuerstenberg ECDIS site – comprehensive information on ECDIS basics, chart datum, ENC distribution, ENC organization on board,ENC updating, various ECDIS settings, regulatory documents and publications etc. ECDIS Regs – website for all ECDIS regulations, ECDIS publications and ECDIS documentation
Exmouth Lifeboat Station
Exmouth Lifeboat Station is the base for Royal National Lifeboat Institution search and rescue operations at Exmouth, England. The first lifeboat was stationed in the town in 1803 and the present station was opened in 2009. In 2014 a new Shannon-class 25-knot all-weather boat went on station. Operated is a D-class inshore lifeboat. Vessels trying to reach Topsham and Exeter have to negotiate the sandbanks at the mouth of the River Exe. Local people raised funds with the help of Lloyd's of London to purchase a lifeboat in 1803. A boathouse was built near Passage House but this was washed away in a storm in 1814; the RNLI revived Exmouth Lifeboat Station in 1858. A new boathouse was built near the beach, although the lifeboat had to be taken across the road before it could be launched; this boathouse was demolished and a new one built on the same site in 1903 to accommodate a larger lifeboat. The first motor lifeboat at Exmouth arrived in 1933 and a tractor was provided to speed up the movement across the road and beach for launches.
Exmouth received brand new Liverpool-class Maria Noble on 1 October 1953 but it was not named until 1 September 1954. Her first service call was on the evening 19 September 1954 to investigate flashing lights and shouts for help near the Maer Rocks; the lifeboat secretary and coxswain lit up the scene with a car's headlights and they saw the 20-foot cabin cruiser Nicky, at anchor but appeared to be sinking. The tide was too low to reach it with the lifeboat, but as soon as the water had risen sufficiently it was launched. Now the lifeboat touched the bottom in the troughs between waves; the lifeboat took on board all the people from the Nicky and returned to station just 26 minutes after being launched. Coxswain Harold'Dido' Bradford was awarded the RNLI Bronze Medal for bravery during this rescue. From 1961 the lifeboat was kept afloat in the river near the entrance to Exmouth docks. A boarding boat was kept on a davit, lowered into the water to ferry the crew out to the lifeboat; the old lifeboat station by the beach was retained as a fund-raising display centre and, from 1966, was the base for an inshore lifeboat.
The building used by crews at the docks was demolished in 1996 and replaced by temporary portable buildings. In 2005 trials were made to consider whether it would be possible to return the all-weather boat to the beach boathouse where it would not be hampered by shallow water in the river when it was needed at low tide; as a result of this it was decided to build a new boathouse further along the beach near the Maer Rocks from where both the ALB and ILB could operate at all states of the tide. The Trent-class was exchanged for an interim Mersey-class, small enough to be housed in a boathouse, the new facility was declared operational on 21 November 2009; the Shannon class lifeboat reestablished the 25knot service. The old boathouse was retained as a base for the RNLI lifeguards who work in and around Exmouth. until being handed back to Clinton devon estates, now used by Exmouth Rowing Club. A new D-class inshore lifeboat arrived in 2017. William J Carder was born in 1903 and volunteered for the Exmouth lifeboat crew in June 1953.
He earned a living running The Volunteer public house. On Christmas Day 1956 he was on board when the Maria Noble was called out to the MV Minerva, burning distress flares 4 miles south east of Orcombe Point; the lifeboat launched at 5:20 pm into a Force 6 to 8 wind and 20-foot waves. About 10 minutes out a large wave pushed the boat far over onto her side and the radio aerial was damaged. Will Carder was near the front of the boat with two colleagues at the time and told them that he was going aft to get some shelter. Another large wave broke over the boat. Although no one saw it happen, this is believed to be. Brian Rowsell was trying to repair the aerial and was knocked into the mast and sustained a head injury. A few minutes Second Coxswain Jack Phillips was washed overboard. Coxswain Harold'Dido' Bradford took the decision to continue to the ship, in distress. To turn the lifeboat around to search for the missing men would have been difficult and dangerous in that storm. While the main radio was inoperable, a message was broadcast on the wavelength used by trawlers and this was picked up in Exmouth and relayed to the lifeboat station.
A search was got underway along the beaches. Jack Phillips was found staggering in the surf, he was taken to hospital. The body of Will Carder was found nearby; the lifeboat reached the Minerva at 6:45. They found that the engines had failed and the anchor was holding, they stood by until 8 o'clock. Sea conditions made it difficult to return to their station so they sailed instead to Torquay where Brian Rowsell was taken to hospital to have his injuries seen to; the crew stayed here to rest and returned home at 2 pm on Boxing Day, the RNLI flag flying at half mast. The lifeboat station is built at the eastern end of Queen's Drive at the top of the beach; the building contains two separate boathouses for the ILB and ALB and has a short concrete slipway that leads down to the beach. Each boat is kept on a carriage attached to a tractor which propels it down to the water and brings it back after use. A fund-raising shop is situated on the east side; the Shannon-class at Exmouth has an operating range of 250 nautical miles and a top speed of 25 knots.
Flank all-weather lifeboats are at Weymouth Lifeboat Station to the east, Torbay to the southwest. Inshore area of operation includes the river Exe up to the city of
Eyemouth Lifeboat Station
Eyemouth Lifeboat Station is a Royal National Lifeboat Institution marine-rescue facility in Eyemouth, Scotland. The station was founded in 1876 to protect local fisherman during periods of poor weather conditions; the original lifeboat house built in the town cost £500 to complete, this was replaced in 1908 with a new house and new facilities were completed in 1992 and extended in 2010 at a cost of over £200,000. The station; the station has the RNLB Helen Hastings all weather Shannon-class lifeboat and MYWAY inshore D-class in service. The station has received two medals of recognition, one silver in 1991 and a bronze from 1917. RNLI station page Local History Site with pictures of old Lifeboats and Lifeboat men Facebook page with updates from the current crew and staff
Great Britain is an island in the North Atlantic Ocean off the northwest coast of continental Europe. With an area of 209,331 km2, it is the largest of the British Isles, the largest European island, the ninth-largest island in the world. In 2011, Great Britain had a population of about 61 million people, making it the world's third-most populous island after Java in Indonesia and Honshu in Japan; the island of Ireland is situated to the west of Great Britain, together these islands, along with over 1,000 smaller surrounding islands, form the British Isles archipelago. The island is dominated by a maritime climate with quite narrow temperature differences between seasons. Politically, Great Britain is part of the United Kingdom of Great Britain and Northern Ireland, constitutes most of its territory. Most of England and Wales are on the island; the term "Great Britain" is used to include the whole of England and Wales including their component adjoining islands. A single Kingdom of Great Britain resulted from the union of the Kingdom of England and the Kingdom of Scotland by the 1707 Acts of Union.
In 1801, Great Britain united with the neighbouring Kingdom of Ireland, forming the United Kingdom of Great Britain and Ireland, renamed the "United Kingdom of Great Britain and Northern Ireland" after the Irish Free State seceded in 1922. The archipelago has been referred to by a single name for over 2000 years: the term'British Isles' derives from terms used by classical geographers to describe this island group. By 50 BC Greek geographers were using equivalents of Prettanikē as a collective name for the British Isles. However, with the Roman conquest of Britain the Latin term Britannia was used for the island of Great Britain, Roman-occupied Britain south of Caledonia; the earliest known name for Great Britain is Albion or insula Albionum, from either the Latin albus meaning "white" or the "island of the Albiones". The oldest mention of terms related to Great Britain was by Aristotle, or by Pseudo-Aristotle, in his text On the Universe, Vol. III. To quote his works, "There are two large islands in it, called the British Isles and Ierne".
Pliny the Elder in his Natural History records of Great Britain: "Its former name was Albion. Old French Bretaigne and Middle English Bretayne, Breteyne; the French form replaced the Old English Breoton, Bryten, Breten. Britannia was used by the Romans from the 1st century BC for the British Isles taken together, it is derived from the travel writings of the Pytheas around 320 BC, which described various islands in the North Atlantic as far north as Thule. Marcian of Heraclea, in his Periplus maris exteri, described the island group as αἱ Πρεττανικαὶ νῆσοι; the peoples of these islands of Prettanike were called the Priteni or Pretani. Priteni is the source of the Welsh language term Prydain, which has the same source as the Goidelic term Cruithne used to refer to the early Brythonic-speaking inhabitants of Ireland; the latter were called Picts or Caledonians by the Romans. Greek historians Diodorus of Sicily and Strabo preserved variants of Prettanike from the work of Greek explorer Pytheas of Massalia, who travelled from his home in Hellenistic southern Gaul to Britain in the 4th century BC.
The term used by Pytheas may derive from a Celtic word meaning "the painted ones" or "the tattooed folk" in reference to body decorations. The Greco-Egyptian scientist Ptolemy referred to the larger island as great Britain and to Ireland as little Britain in his work Almagest. In his work, Geography, he gave the islands the names Alwion and Mona, suggesting these may have been the names of the individual islands not known to him at the time of writing Almagest; the name Albion appears to have fallen out of use sometime after the Roman conquest of Britain, after which Britain became the more commonplace name for the island. After the Anglo-Saxon period, Britain was used as a historical term only. Geoffrey of Monmouth in his pseudohistorical Historia Regum Britanniae refers to the island as Britannia major, to distinguish it from Britannia minor, the continental region which approximates to modern Brittany, settled in the fifth and sixth centuries by migrants from Britain; the term Great Britain was first used in 1474, in the instrument drawing up the proposal for a marriage between Cecily the daughter of Edward IV of England, James the son of James III of Scotland, which described it as "this Nobill Isle, callit Gret Britanee".
It was used again in 1604, when King James VI and I styled himself "King of Great Brittaine and Ireland". Great Britain refers geographically to the island of Great Britain, it is often used to refer politically to the whole of England and Wales, including their smaller off shore islands. While it is sometimes used to refer to the whole of the United Kingdom, including Northern Ireland, this is not correct. Britain can refer to either all island