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Lesson 28

Summer Sports: Scuba Diving

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Scuba diving is a wonderful summer outdoor activity adored by innumerable men and women across the globe. But like many outdoor activities, it is also inherently dangerous sport, which can only be performed in relative safety if you get proper training.

Scuba Diving is not just a swim in the water; scuba requires certification and uses technical equipment. Scuba, which is actually an acronym for "self-contained breathing apparatus", allows divers to dive deeper and stays, submerged longer. Modern scuba diving gear consists of one or more gas tanks strapped to the divers back, connected to an air hose and an invention called the demand regulator. The demand regulator controls the flow of air, so that the air pressure within the diver's lungs equals the pressure of the water.

The desire to go under water has probably always existed: to hunt for food, uncover artifacts, repair ships (or sink them!), and perhaps just to observe marine life. Until humans found a way to breathe underwater, however, each dive was necessarily short and frantic.

Men and women have practiced breath-hold diving for centuries. Indirect evidence comes from ancient artifacts of undersea origin found on land and depictions of divers in ancient drawings. Perhaps the earliest reference to scuba diving is a 3000-year-old Assyrian fresco that shows men swimming under water, using some kind of breathing device.

In ancient Greece breath-hold divers are known to have hunted for sponges and engaged in military exploits. The writings of Homer mention Greek sponge fishermen who plummet to depths of almost 30 meters (100 feet) by holding a heavy rock. They knew little about the physical dangers of diving. To try and compensate for the increasing pressure on their ears, they poured oil into their ear canals and took a mouthful before descent. Once on the bottom, they spit out the oil, cut as many sponges free from the bottom as their breath would allow, and were then hauled back to the surface by a tether.

Of the latter, the story of Scyllis (sometimes spelled Scyllias; about 500 BC) is perhaps the most famous, as told by the 5th century B.C. Greek historian Herodotus (and quoted in numerous modern texts). During a naval campaign the Greek Scyllis was taken aboard ship as prisoner by the Persian King Xerxes I. When Scyllis learned that Xerxes was to attack a Greek flotilla, he seized a knife and jumped overboard. The Persians could not find him in the water and presumed he had drowned. Scyllis surfaced at night and made his way among all the ships in Xerxes's fleet, cutting each ship loose from its moorings; he used a hollow reed as snorkel to remain unobserved. Then he swam nine miles (15 kilometers) to rejoin the Greeks off Cape Artemisium.

Divers probably began using snorkels made of hollow reeds about 100 A.D. as the first piece of diving equipment. Breathing through a hollow reed allows the body to be submerged, but it must have become apparent right away that reeds more than two feet long do not work well; difficulty inhaling against water pressure effectively limits snorkel length. Breathing from an air-filled bag brought under water was also tried, but it failed due to rebreathing of carbon dioxide.

Aristotle describes a "Diving Bell," purportedly used by Alexander the Great in 332 BC. The diving bell concept was experimented with for centuries until the first documented self-contained Underwater Breathing Apparatus appeared: Leonardo Da Vinci designs a freestanding system that includes an air supply and a means of buoyancy control in the 1500's. There is no proof that it was ever actually manufactured, but it clearly heralded the birth of the SCUBA.

In the 16th century people began to use diving bells supplied with air from the surface, probably the first effective means of staying under water for any length of time. The bell was held stationary a few feet from the surface, its bottom open to water and its top portion containing air compressed by the water pressure. A diver standing upright would have his head in the air. He could leave the bell for a minute or two to collect sponges or explore the bottom, then return for a short while until air in the bell was no longer breathable.

In 1819 German inventor August Siebe developed the first diving suit - a copper helmet attached to a canvas and leather suit. Hoses supplied air to the diver by a surface pump. The hoses were attached to the helmet, and the pressure the air provided kept the water level below the diver's chin. Weights worn around the chest kept the diver from rising to the surface when more air was supplied to the helmet. Siebe's suit freed divers to explore the bottom of the sea on foot, and windows in the helmet increased what divers could see.

In 1943, Frenchmen, Emile Gagnan and Jacques Cousteau invented the demand regulator, which adjusted the air pressure automatically, supplying air, as the diver needed it. Together, Gagnan and Cousteau further improved the designs of diving equipment. Their regulator was connected to three cylinders, each holding 2,500 psi of air. The complete equipment, or autonomous diving suit with the pressure regulator, was called the "Aqua-lung". The "Aqua-lung" is the basis for modern equipment used today, most historians refer to Gagnan and Cousteau as the fathers of modern scuba diving gear.

Scuba diving grew somewhat slowly through the late 40's and early 50's because, although the diver could now stay underwater for an extended period of time, in most parts of the world the water was so cold that he was forced to leave the water after a short time. In the early 1950's, rubber suits were designed. They were used to keep the diver warm. These old "dry suits" were worn over long underwear and sweat suits or sweaters. The clothing acted as an insulator, and the rubber suit was used to simply keep the insulation dry. Nowadays, neoprene is used for all wet suits.

Emergency equipment of scuba divers includes a dive knife, in case the diver becomes entangled in fishing line or marine plants, whistles, lights, or signaling devices, in case the diver is lost or swept out in a current, a marine radio and a first aid kit.

Most marine animals pose no threat to divers. In fact, divers pose far more threat to the animals. A diver's single touch, for example, can kill coral. However, a few forms of marine life can injure divers. Jellyfish, fire coral, stinging coral, and sea urchins are the most common threats. In rare cases, poisonous fish and sharks can also injure people. In general, animals only attack humans when they are provoked. Scuba diving should be a visual experience, and divers should avoid touching anything - plant, animal, or object.

Many aspiring scuba divers switch-on their days of marine adventure by donning mask, snorkel and fins and skimming across acres of water, faces planted downwards and eyes a-goggle at what dwells below. Once hooked and feeling bereaved at their gill-less state, enthusiasts look for the next steps in the diving evolution ladder - the sacrosanct dive course.

Scuba diving involves travel and adventure in exotic places, including new experiences with different cultures. The obsession for the sport of scuba diving has encouraged almost all the tourist destinations to play, practice and teach it.

There are many places around the world that teach scuba. The foremost in this regard are the Caribbean and the Bahamas. Both the places have a volley of beaches that keep the divers busy throughout the year. Amongst the coveted destinations to dive are also 'The Great Barrier Reef' and 'The Coral Sea'. And when it comes to Australia, the country is brimming up with the divers almost the entire year.

Not to be overlooked are the crystal blue beaches of Florida and Hawaii that are vibrant especially during the winters. Besides these, the American area from Latin to South America is a perfect host for scuba diving.

Scuba diving resorts have special instructors that guide you to develop the some basic skills of the sport. It is the best way to learn without casting your life to danger.


Vocabulary
  1. scuba - леководолазен дихателен апарат
  2. diving - гмуркане; сп. скок във вода
  3. submerged - потопен
  4. gear - механизъм
  5. tank - цистерна, резервоар
  6. to strap (-pp-) - привързвам, пристягам с ремък, каиш(ка) и пр.
  7. hose - маркуч
  8. flow - поток, струя
  9. artifact - археол. артифакт, предмет изработен от човешка ръка
  10. to sink [sank, sunk] - потъвам; потапям (се)
  11. marine life - морска флора и фауна
  12. frantic - безумен
  13. depiction - рисунка, изображение
  14. sponge - гъба, сюнгер
  15. exploit - подвиг, геройство
  16. plummet - падам право надолу
  17. to pour - сипвам, изсипвам
  18. mouthful - 1. хапка, глътка; 2. малко количество
  19. descent - спускане, слизане
  20. to spit out - изплювам
  21. to houl - влача, тегля, изтеглям
  22. tether - въже/верига
  23. of the latter - второ, на второ място
  24. to seize - хващам, сграбчвам
  25. to drown - давя (се), удавям (се)
  26. fleet - флота; военноморски флот
  27. moorings - мор. съоръжения/място за акостриране/пускане на котва
  28. hollow - кух, празен
  29. reed - тръстика, тръстиково стъбло
  30. snorkel - шнорхел
  31. buoyancy - способност за задържане на повърхността на водата
  32. to herald - известявам, възвестявам
  33. diving suit - водолазен костюм
  34. copper - меден
  35. helmet - шлем, каска
  36. canvas - ленено/конопено платно
  37. leather - кожен
  38. sweat suit - спортен екип (клин и анцуг)
  39. insulator - изолатор
  40. emergency - непредвиден/спешен случай
  41. to entangle - вплитам, уплитам, омотавам
  42. whistle - свирка
  43. to sweep out - завличам, помитам
  44. current - течение
  45. first aid kit - екип(ировка), принадлежности; комплект инструменти за оказване на първа помощ
  46. to pose - представлявам (проблем, затруднение, заплаха)
  47. jellyfish - медуза
  48. stinging - който жили/пари
  49. sea urchin - морски таралеж
  50. poisonous - отровен
  51. aspiring - амбициозен
  52. to don(-nn-) - обличам, надявам
  53. fin - плавник
  54. to skim (-mm-) - плъзгам се, нося се
  55. to goggle (v) - гледам с широко отворени/ококорени очи; goggle (n) - pl. очила за слънце (на водолаз и пр.); sl. очила
  56. to dwell [dwelt, dwelled] - живея
  57. to be/get hooked on - пристрастявам се към (нещо)
  58. to bereave [pt. pp. bereaved] - съкрушавам, правя безутешен; осиротявам
  59. gill - обикн. pl. хриле
  60. sacrosanct - свещен, неприкосновен
  61. foremost - най-важен/изтъкнат/главен
  62. volley - прен. поток, порой
  63. coveted - желан
  64. to brim(-mm-) - препълнен съм, преливам
  65. to overlook - пропускам, прескачам незабелязано; гледам със снизхождение
  66. vibrant - изпълнен с живот/жизненост; оживен   67. resort - курорт

 Pour, Pore or Poor


Key terms:  

  • SCUBA - self-contained underwater breathing apparatus
  • SCUBA diving - a method of viewing coral reefs underwater for extended periods of time; diving into depths of the water using a Self-Contained Underwater Breathing Apparatus.
  • demand regulator - in reference to SCUBA diving equipment, a device which allows compressed air to flow from the tanks to the mouth of a diver.
  • diving bell - a weighted chamber, open at the bottom, in which a person can be lowered under water.
  • neoprene - a man made fabric, used for wetsuits and other water sports attire. Has a stiff, body hugging quality that seals body heat in.
  • snorkel - a hollow tube swimmers or divers can breathe through when they are close to the surface
  • mask - a covering of the eyes and nose that allows the clear viewing of underwater environments.
  • fins - plastic or wooden attachments to the foot that adds strength to the kick of a swimmer.
  • marinelife - animals that live in the ocean including coral polyps, sea urchins, clams, shells, worms, crabs, octopuses, squid, etc.
  • buoyancy - the ability or tendency of a marine organism to float. Sharks are buoyant because of the oil contained in their over-sized livers.
  • coral reef - a collective structure consisting of dead skeletal limestone that has accumulated over time and a result of the coral animals that cover the structure's surface. As a result of a series of ecological relationships, the coral reef structure is directly responsible for the production of much of the earth's fish and marinelife.
  • barrier reef - a type of coral reef that lies parallel to a beach shoreline and protects a lagoon.
  • resorts - places where entertainment, accommodation, meals and marine activities take place.


Coral Reefs

Coral reefs are essentially immense limestone structures that take many thousands of years to grow. They entered the geological record about 370 million years ago during the Paleozoic era. There are currently over 800 identified varieties of coral. Many contemporary reef systems are between 5,000 and 10,000 years old. They consist of millions of coral polyps, a community of marine invertebrates that produce a calcium carbonate skeleton. Each time a polyp dies, new polyps surround and replace the dead ones. These layers of dead polyps compress and build up over time, forming the reef. Coral reefs grow only in pristine, warm, saline rich waters. They can’t tolerate fresh water, and require stable temperatures between 70° and 85°. Although some species of coral are found as deep as 300 feet, most grow poorly in waters below 90 feet, due to the inability of sunlight to permeate deep water.

Coral reefs can be found in over 100 countries worldwide, yet they occupy less than one tenth of one percent of the oceans. The most recent approximation asserts that just over 100,000 square miles of coral reefs exist on the planet. Although they cover less than .01% of the planet, scientists estimate that coral reefs provide shelter for nearly 1/4 of all marine species that exist today. The natural resources and resulting industries provided by reef systems to the nearby regions are worth nearly 400 billion dollars each year: a astonishing amount for an ecosystem that covers an area about the size of the state of Arizona. In addition to the tourism related industries, coral reefs serve as barriers against storms, act as spawning grounds for countless species of fish, and supply compounds for life-giving pharmaceuticals. Drugs derived from reef life are being used to treat cancer, tumors, arthritis, bacterial infections, viruses, ulcers, immune diseases, and even broken bones. More critically, coral reefs provide the primary source of food for nearly 2 billion people around the world.

Source: Florida Scubahound - diving on Coral Reefs

1. limestone - варовик
2. invertebrate - безгръбначно животно
3. pristine - девствен, чист
4. saline - солен
5. to permeate - прониквам, разпространявам се
6. to assert - твърдя, заявявам
7. to spawn - хвърлям хайвера си
8. ulcer - мед. язва

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