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Caving Equipment
Caving equipment is equipment used by cavers and speleologists to aid and protect them while exploring caves. The term may also be used to refer to equipment used to document caves, such as photographic and surveying equipment. Originally, cave diving equipment was quite limited, but the increasing popularity of caving during the 20th century led to the creation of specialist caving equipment and companies. Due to the greatly varying conditions of caves throughout the world there is a multitude of different equipment types and categories. Cavers exploring a largely dry system may wear a fleece one-piece undersuit with a protective oversuit while cavers exploring a very wet cave may opt to use wetsuits. Cavers in large dry systems in the tropics and in desert climates may simply opt to wear shorts and a T-shirt. History The earliest cavers in Europe and North America were limited in their explorations by a lack of suitable equipment. Explorers of the early 1800s, when caving beg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marble Arch Cave
The Marble Arch Caves are a series of natural limestone caves located near the village of Florencecourt in County Fermanagh, Northern Ireland. The caves are named after the nearby Marble Arch, a natural limestone arch at the upstream end of Cladagh Glen under which the Cladagh River flows. The caves are formed from three rivers draining off the northern slopes of Cuilcagh mountain, which combine underground to form the Cladagh. On the surface, the river emerges from the largest karst resurgence in Ireland, and one of the largest in the United Kingdom. At the Marble Arch Caves form the longest known cave system in Northern Ireland, and the karst is considered to be among the finest in the British Isles. History 18th–19th century: The Junction, Grand Gallery, and Pool Chamber The Marble Arch, Cladagh River resurgence and three large dolines on the plateau above the end of Cladagh Glen were all known well before underground exploration began; in fact the arch was a popul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nylon
Nylon is a generic designation for a family of synthetic polymers composed of polyamides ( repeating units linked by amide links).The polyamides may be aliphatic or semi-aromatic. Nylon is a silk-like thermoplastic, generally made from petroleum, that can be melt-processed into fibers, films, or shapes. Nylon polymers can be mixed with a wide variety of additives to achieve many property variations. Nylon polymers have found significant commercial applications in fabric and fibers (apparel, flooring and rubber reinforcement), in shapes (molded parts for cars, electrical equipment, etc.), and in films (mostly for food packaging). History DuPont and the invention of nylon Researchers at DuPont began developing cellulose based fibers, culminating in the synthetic fiber rayon. DuPont's experience with rayon was an important precursor to its development and marketing of nylon. DuPont's invention of nylon spanned an eleven-year period, ranging from the initial research pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dent De Crolles
The Dent de Crolles () is a karstic mountain (2,062 m) of the Chartreuse Mountains range, north east of Grenoble, Isère, France. It has a characteristic "tooth-like" profile and is easily recognizable in the Isère Valley (Grésivaudan) in the Grenoble area. The French word "dent" means tooth and "de Crolles" is derived from the town of Crolles, located next to the mountain. Geography The Dent de Crolles is a karstic mountain (2,062 m) of the Chartreuse Mountains range, north east of Grenoble, Isère, France. The French word "dent" means tooth and "de Crolles" is derived from the town of Crolles, located next to the mountain. It is easily recognizable from the Val-d´Isère (Grésivaudan) in the Grenoble area. Cave system The réseau de la Dent de Crolles, which lies beneath the summit plateau, is one of the most complex and longest cave systems in Europe, and is considered to be one of the birth places of modern caving. Its first detailed exploration was during World War II b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pierre Chevalier (caver)
Pierre Chevalier (24 April 1905 – 4 December 2001) was a well-known caver and mountaineer from France, with many alpine ascents and cave explorations to his credit. Chevalier is principally known for the exploration of the Dent de Crolles cave system over a twelve-year period (1936 – 1947), which became the deepest cave in the world. Chevalier recorded this exploration in his book ''Escalades souterraines'' (''Subterranean Climbers''). Dent de Crolles Cave Network Chevalier first visited the Trou du Glaz entrance in 1935, and was struck by the possibility of exploring beyond what was at the time considered technically possible. With Fernand Petzl, Charles Petit-Didier and others, Chevalier completed explorations that connected four entrances (Trou du Glaz, Guiers Mort, P40 and Grotte Annette) and established the Dent de Crolles as the deepest cave system in the world (-658m). Much of this exploration was during the German occupation of France during the Second World War and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gouffre Berger
The Gouffre Berger is a French cave discovered on 24 May 1953 by Joseph Berger, Bouvet, Ruiz de Arcaute and Marc Jouffrey. From 1953 to 1963, it was regarded as the deepest cave in the world at , relinquishing this title to the previous contender, Pierre Saint Martin, in 1964, after further exploration. The Gouffre Berger is now ranked 37th deepest cave in the world, and the 4th in France. To return from the bottom of the cave back to the surface can take between 15 and 30 hours, without long breaks. In 1967, Ken Pearce, a metallurgy lecturer from Britain, descended with the Pegasus Caving Club team from Nottingham UK, organised and led by Peter Watkinson, and along with a dive, reached a depth of . They emerged after 13 days underground, having set a new world record at the time. In 1968, B Leger and J Dubois reached a depth of . This record was held until July 1982, when Patrick Penez attained . In 1990, a breakthrough was made, connecting the cave to the nearby "Scialet de la ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aluminium
Aluminium (aluminum in American and Canadian English) is a chemical element with the symbol Al and atomic number 13. Aluminium has a density lower than those of other common metals, at approximately one third that of steel. It has a great affinity towards oxygen, and forms a protective layer of oxide on the surface when exposed to air. Aluminium visually resembles silver, both in its color and in its great ability to reflect light. It is soft, non-magnetic and ductile. It has one stable isotope, 27Al; this isotope is very common, making aluminium the twelfth most common element in the Universe. The radioactivity of 26Al is used in radiodating. Chemically, aluminium is a post-transition metal in the boron group; as is common for the group, aluminium forms compounds primarily in the +3 oxidation state. The aluminium cation Al3+ is small and highly charged; as such, it is polarizing, and bonds aluminium forms tend towards covalency. The strong affinity tow ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Robert De Joly
Robert-Jacques de Joly (, Paris – , Montpellier) was a famous French caver and speleologist. Considered by some as the successor to Édouard-Alfred Martel (the "father of modern speleology"), de Joly was a leading figure of French speleology between the world wars (along with Norbert Casteret) and into the 1960s. De Joly was an active cave explorer throughout his entire life, from age fourteen until shortly before his death at the age of eighty. He was known for his physical strength and strong personality, and was responsible for inspiring and training many successful and influential cavers. De Joly is credited with the invention of the lightweight, portable steel-cable ('electron') ladder, a tool that expanded the possibilities of cave explorations and became standard caving equipment for the next fifty years. Amongst his numerous explorations was the , one of the most beautiful caves in France, later developed into a show cave A show cave—also called tourist cave, pu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Donkey
The domestic donkey is a hoofed mammal in the family Equidae, the same family as the horse. It derives from the African wild ass, ''Equus africanus'', and may be classified either as a subspecies thereof, ''Equus africanus asinus'', or as a separate species, ''Equus asinus''. It was domesticated in Africa some years ago, and has been used mainly as a working animal since that time. There are more than 40 million donkeys in the world, mostly in underdeveloped countries, where they are used principally as draught or pack animals. While working donkeys are often associated with those living at or below subsistence, small numbers of donkeys or asses are kept for breeding or as pets in developed countries. A male donkey is known as a ''jack'' or ''jackass'', a female is a ''jenny'' or ''jennet'', and an immature donkey of either sex is a '' foal''. Jacks are often mated with female horses (mares) to produce '' mules''; the less common hybrid of a male horse (stallion) and j ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rope Ladder
A rope is a group of yarns, plies, fibres, or strands that are twisted or braided together into a larger and stronger form. Ropes have tensile strength and so can be used for dragging and lifting. Rope is thicker and stronger than similarly constructed cord, string, and twine. Construction Rope may be constructed of any long, stringy, fibrous material, but generally is constructed of certain natural or synthetic fibres. Synthetic fibre ropes are significantly stronger than their natural fibre counterparts, they have a higher tensile strength, they are more resistant to rotting than ropes created from natural fibres, and they can be made to float on water. But synthetic ropes also possess certain disadvantages, including slipperiness, and some can be damaged more easily by UV light. Common natural fibres for rope are Manila hemp, hemp, linen, cotton, coir, jute, straw, and sisal. Synthetic fibres in use for rope-making include polypropylene, nylon, polyesters (e.g. PET, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
LED Light
An LED lamp or LED light bulb is an electric light that produces light using light-emitting diodes (LEDs). LED lamps are significantly more energy-efficient than equivalent incandescent lamps and can be significantly more efficient than most fluorescent lamps. The most efficient commercially available LED lamps have efficiencies of 200 lumen per watt (Lm/W). Commercial LED lamps have a lifespan many times longer than incandescent lamps. LED lamps require an electronic LED driver circuit to operate from mains power lines, and losses from this circuit means that the efficiency of the lamp is lower than the efficiency of the LED chips it uses. The driver circuit may require special features to be compatible with lamp dimmers intended for use on incandescent lamps. Generally the current waveform contains some amount of distortion, depending on the luminaires’ technology. The LED lamp market is projected to grow from US$75.8 billion in 2020 and increasing to US$160 billion in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
