document_title: Great Pyramid of Giza

question_text: what was written on the walls of the king's chamber

question_tokens: what was written on the walls of the king 's chamber

text: Great Pyramid of Giza

text: History and description

text: It is believed[by whom?] the pyramid was built as a tomb for Fourth Dynasty Egyptian pharaoh Khufu (often Hellenicised as "Cheops") and was constructed over a 20-year period. Khufu's vizier, Hemiunu (also called Hemon), is believed by some to be the architect of the Great Pyramid.[3] It is thought that, at construction, the Great Pyramid was originally 280 Egyptian cubits tall (146.5 metres (480.6 ft)), but with erosion and absence of its pyramidion, its present height is 138.8 metres (455.4 ft). Each base side was 440 cubits, 230.4 metres (755.9 ft) long. The mass of the pyramid is estimated at 5.9 million tonnes. The volume, including an internal hillock, is roughly 2,500,000 cubic metres (88,000,000 cu ft).[4]

text: Based on these estimates, building the pyramid in 20 years would involve installing approximately 800 tonnes of stone every day. Additionally, since it consists of an estimated 2.3 million blocks, completing the building in 20 years would involve moving an average of more than 12 of the blocks into place each hour, day and night. The first precision measurements of the pyramid were made by Egyptologist Sir Flinders Petrie in 1880–82 and published as The Pyramids and Temples of Gizeh.[5] Almost all reports are based on his measurements. Many of the casing stones and inner chamber blocks of the Great Pyramid fit together with extremely high precision. Based on measurements taken on the northeastern casing stones, the mean opening of the joints is only 0.5 millimetre wide (1/50 of an inch).[6]

text: The pyramid remained the tallest man-made structure in the world for over 3,800 years,[7] unsurpassed until the 160-metre-tall (520 ft) spire of Lincoln Cathedral was completed c. 1300. The accuracy of the pyramid's workmanship is such that the four sides of the base have an average error of only 58 millimetres in length.[8] The base is horizontal and flat to within ±15 mm (0.6 in).[9] The sides of the square base are closely aligned to the four cardinal compass points (within four minutes of arc)[10] based on true north, not magnetic north,[11] and the finished base was squared to a mean corner error of only 12 seconds of arc.[12]

text: The completed design dimensions, as suggested by Petrie's survey and subsequent studies, are estimated to have originally been 280 royal cubits high by 440 cubits long at each of the four sides of its base. The ratio of the perimeter to height of 1760/280 royal cubits equates to 2π to an accuracy of better than 0.05% (corresponding to the well-known approximation of π as 22/7). Some Egyptologists consider this to have been the result of deliberate design proportion. Verner wrote, "We can conclude that although the ancient Egyptians could not precisely define the value of π, in practice they used it".[13] Petrie, author of Pyramids and Temples of Gizeh concluded: "but these relations of areas and of circular ratio are so systematic that we should grant that they were in the builder's design".[14] Others have argued that the Ancient Egyptians had no concept of pi and would not have thought to encode it in their monuments. They believe that the observed pyramid slope may be based on a simple seked slope choice alone, with no regard to the overall size and proportions of the finished building.[15] In 2013 rolls of papyrus called The diary of Merer were discovered written by some of those who delivered stone and other construction materials to Khufu's brother at Giza.[16]

text: Materials

text: The Great Pyramid consists of an estimated 2.3 million blocks which most believe to have been transported from nearby quarries. The Tura limestone used for the casing was quarried across the river. The largest granite stones in the pyramid, found in the "King's" chamber, weigh 25 to 80 tonnes and were transported from Aswan, more than 800 km (500 mi) away. Traditionally, ancient Egyptians cut stone blocks by hammering into them some wooden wedges, which were then soaked with water. As the water was absorbed, the wedges expanded, causing the rock to crack. Once they were cut, they were carried by boat either up or down the Nile River to the pyramid.[17] It is estimated that 5.5 million tonnes of limestone, 8,000 tonnes of granite (imported from Aswan), and 500,000 tonnes of mortar were used in the construction of the Great Pyramid.[18]

text: Casing stones

text: At completion, the Great Pyramid was surfaced by white "casing stones" – slant-faced, but flat-topped, blocks of highly polished white limestone. These were carefully cut to what is approximately a face slope with a seked of 5½ palms to give the required dimensions. Visibly, all that remains is the underlying stepped core structure seen today. In AD 1303, a massive earthquake loosened many of the outer casing stones, which were then carted away by Bahri Sultan An-Nasir Nasir-ad-Din al-Hasan in 1356 to build mosques and fortresses in nearby Cairo. Many more casing stones were removed from the great pyramids by Muhammad Ali Pasha in the early 19th century to build the upper portion of his Alabaster Mosque in Cairo not far from Giza. These limestone casings can still be seen as parts of these structures. Later explorers reported massive piles of rubble at the base of the pyramids left over from the continuing collapse of the casing stones, which were subsequently cleared away during continuing excavations of the site.

text: Nevertheless, a few of the casing stones from the lowest course can be seen to this day in situ around the base of the Great Pyramid, and display the same workmanship and precision that has been reported for centuries. Petrie also found a different orientation in the core and in the casing measuring 193 centimetres ± 25 centimetres. He suggested a redetermination of north was made after the construction of the core, but a mistake was made, and the casing was built with a different orientation.[5] Petrie related the precision of the casing stones as to being "equal to opticians' work of the present day, but on a scale of acres" and "to place such stones in exact contact would be careful work; but to do so with cement in the joints seems almost impossible".[20] It has been suggested it was the mortar (Petrie's "cement") that made this seemingly impossible task possible, providing a level bed, which enabled the masons to set the stones exactly.[21][22]

text: Construction theories

text: Many alternative, often contradictory, theories have been proposed regarding the pyramid's construction techniques.[23] Many disagree on whether the blocks were dragged, lifted, or even rolled into place. The Greeks believed that slave labour was used, but modern discoveries made at nearby workers' camps associated with construction at Giza suggest that it was built instead by tens of thousands of skilled workers. Verner posited that the labour was organized into a hierarchy, consisting of two gangs of 100,000 men, divided into five zaa or phyle of 20,000 men each, which may have been further divided according to the skills of the workers.[24]

text: One mystery of the pyramid's construction is its planning. John Romer suggests that they used the same method that had been used for earlier and later constructions, laying out parts of the plan on the ground at a 1-to-1 scale. He writes that "such a working diagram would also serve to generate the architecture of the pyramid with precision unmatched by any other means".[25] He also argues for a 14-year time span for its construction.[26] A modern construction management study, in association with Mark Lehner and other Egyptologists, estimated that the total project required an average workforce of about 14,500 people and a peak workforce of roughly 40,000. Without the use of pulleys, wheels, or iron tools, they used critical path analysis methods, which suggest that the Great Pyramid was completed from start to finish in approximately 10 years.[27]

text: Interior

text: The original entrance to the Great Pyramid is on the north, 17 metres (56 ft) vertically above ground level and 7.29 metres (23.9 ft) east of the centre line of the pyramid. From this original entrance, there is a Descending Passage 0.96 metres (3.1 ft) high and 1.04 metres (3.4 ft) wide, which goes down at an angle of 26° 31'23" through the masonry of the pyramid and then into the bedrock beneath it. After 105.23 metres (345.2 ft), the passage becomes level and continues for an additional 8.84 metres (29.0 ft) to the lower Chamber, which appears not to have been finished. There is a continuation of the horizontal passage in the south wall of the lower chamber; there is also a pit dug in the floor of the chamber. Some Egyptologists suggest that this Lower Chamber was intended to be the original burial chamber, but Pharaoh Khufu later changed his mind and wanted it to be higher up in the pyramid.[28]

text: 28.2 metres (93 ft) from the entrance is a square hole in the roof of the Descending Passage. Originally concealed with a slab of stone, this is the beginning of the Ascending Passage. The Ascending Passage is 39.3 metres (129 ft) long, as wide and high as the Descending Passage and slopes up at almost precisely the same angle to reach the Grand Gallery. The lower end of the Ascending Passage is closed by three huge blocks of granite, each about 1.5 metres (4.9 ft) long. One must use the Robbers' Tunnel (see below) to access the Ascending Passage. At the start of the Grand Gallery on the right-hand side there is a hole cut in the wall. This is the start of a vertical shaft which follows an irregular path through the masonry of the pyramid to join the Descending Passage. Also at the start of the Grand Gallery there is the Horizontal Passage leading to the "Queen's Chamber". The passage is 1.1m (3'8") high for most of its length, but near the chamber there is a step in the floor, after which the passage is 1.73 metres (5.7 ft) high.

text: Queen's Chamber

text: The "Queen's Chamber"[2] is exactly halfway between the north and south faces of the pyramid and measures 5.75 metres (18.9 ft) north to south, 5.23 metres (17.2 ft) east to west, and has a pointed roof with an apex 6.23 metres (20.4 ft) above the floor. At the eastern end of the chamber there is a niche 4.67 metres (15.3 ft) high. The original depth of the niche was 1.04 metres (3.4 ft), but has since been deepened by treasure hunters.[citation needed]

text: In the north and south walls of the Queen's Chamber there are shafts, which unlike those in the King's Chamber that immediately slope upwards (see below), are horizontal for around 2 m (6.6 ft) before sloping upwards. The horizontal distance was cut in 1872 by a British engineer, Waynman Dixon, who believed a shaft similar to those in the King's Chamber must also exist. He was proved right, but because the shafts are not connected to the outer faces of the pyramid or the Queen's Chamber, their purpose is unknown. At the end of one of his shafts, Dixon discovered a ball of black diorite (a type of rock) and a bronze implement of unknown purpose. Both objects are currently in the British Museum.[29]

text: The shafts in the Queen's Chamber were explored in 1993 by the German engineer Rudolf Gantenbrink using a crawler robot he designed, Upuaut 2. After a climb of 65 m (213 ft),[30] he discovered that one of the shafts was blocked by limestone "doors" with two eroded copper "handles". Some years later the National Geographic Society created a similar robot which, in September 2002, drilled a small hole in the southern door, only to find another door behind it.[31] The northern passage, which was difficult to navigate because of twists and turns, was also found to be blocked by a door.[32]

text: Research continued in 2011 with the Djedi Project. Realizing the problem was that the National Geographic Society's camera was only able to see straight ahead of it, they instead used a fiber-optic "micro snake camera" that could see around corners. With this they were able to penetrate the first door of the southern shaft through the hole drilled in 2002, and view all the sides of the small chamber behind it. They discovered hieroglyphs written in red paint. They were also able to scrutinize the inside of the two copper "handles" embedded in the door, and they now believe them to be for decorative purposes. They also found the reverse side of the "door" to be finished and polished, which suggests that it was not put there just to block the shaft from debris, but rather for a more specific reason.[33]

text: Grand Gallery

text: The Grand Gallery continues the slope of the Ascending Passage, but is 8.6 metres (28 ft) high and 46.68 metres (153.1 ft) long. At the base it is 2.06 metres (6.8 ft) wide, but after 2.29 metres (7.5 ft) the blocks of stone in the walls are corbelled inwards by 7.6 centimetres (3.0 in) on each side. There are seven of these steps, so, at the top, the Grand Gallery is only 1.04 metres (3.4 ft) wide. It is roofed by slabs of stone laid at a slightly steeper angle than the floor of the gallery, so that each stone fits into a slot cut in the top of the gallery like the teeth of a ratchet. The purpose was to have each block supported by the wall of the Gallery rather than resting on the block beneath it, which would have resulted in an unacceptable cumulative pressure at the lower end of the Gallery.[citation needed]

text: At the upper end of the Gallery on the right-hand side there is a hole near the roof that opens into a short tunnel by which access can be gained to the lowest of the Relieving Chambers. The other Relieving Chambers were discovered in 1837-1838 by Colonel Howard Vyse and J. S. Perring, who dug tunnels upwards using blasting powder.

text: The floor of the Grand Gallery consists of a shelf or step on either side, 51 centimetres (20 in) wide, leaving a lower ramp 1.04 metres (3.4 ft) wide between them. In the shelves there are 54 slots, 27 on each side matched by vertical and horizontal slots in the walls of the Gallery. These form a cross shape that rises out of the slot in the shelf. The purpose of these slots is not known, but the central gutter in the floor of the Gallery, which is the same width as the Ascending Passage, has led to speculation that the blocking stones were stored in the Grand Gallery and the slots held wooden beams to restrain them from sliding down the passage.[34] This, in turn, has led to the proposal that originally many more than 3 blocking stones were intended, to completely fill the Ascending Passage.[citation needed]

text: At the top of the Grand Gallery, there is a step giving onto a horizontal passage some metres long and approximately 1.02 metres (3.3 ft) in height and width, in which can be detected four slots, three of which were probably intended to hold granite portcullises. Fragments of granite found by Petrie in the Descending Passage may have come from these now-vanished doors.

text: King's Chamber

text: The "King's Chamber"[2] is 20 cubits or 10.47 metres (34.4 ft) from east to west and 10 cubits or 5.234 metres (17.17 ft) north to south. It has a flat roof 11 cubits and 5 digits or 5.852 metres (19 feet 2 inch) above the floor. 0.91 m (3.0 ft) above the floor there are two narrow shafts in the north and south walls (one is now filled by an extractor fan in an attempt to circulate air inside the pyramid). The purpose of these shafts is not clear: they appear to be aligned towards stars or areas of the northern and southern skies, yet one of them follows a dog-leg course through the masonry, indicating no intention to directly sight stars through them. They were long believed by Egyptologists to be "air shafts" for ventilation, but this idea has now been widely abandoned in favour of the shafts serving a ritualistic purpose associated with the ascension of the king’s spirit to the heavens.[35]

text: The King's Chamber is entirely faced with granite. Above the roof, which is formed of nine slabs of stone weighing in total about 400 tons, are five compartments known as Relieving Chambers. The first four, like the King's Chamber, have flat roofs formed by the floor of the chamber above, but the final chamber has a pointed roof. Vyse suspected the presence of upper chambers when he found that he could push a long reed through a crack in the ceiling of the first chamber. From lower to upper, the chambers are known as "Davison's Chamber", "Wellington's Chamber", "Nelson's Chamber", "Lady Arbuthnot's Chamber", and "Campbell's Chamber". It is believed that the compartments were intended to safeguard the King's Chamber from the possibility of a roof collapsing under the weight of stone above the Chamber. As the chambers were not intended to be seen, they were not finished in any way and a few of the stones still retain masons' marks painted on them. One of the stones in Campbell's Chamber bears a mark, apparently the name of a work gang.[36][37]

text: The only object in the King's Chamber is a rectangular granite sarcophagus, one corner of which is broken. The sarcophagus is slightly larger than the Ascending Passage, which indicates that it must have been placed in the Chamber before the roof was put in place. Unlike the fine masonry of the walls of the Chamber, the sarcophagus is roughly finished, with saw marks visible in several places. This is in contrast with the finely finished and decorated sarcophagi found in other pyramids of the same period. Petrie suggested that such a sarcophagus was intended but was lost in the river on the way north from Aswan and a hurriedly made replacement was used instead.

text: Modern entrance

text: Today tourists enter the Great Pyramid via the Robbers' Tunnel, a tunnel purportedly created around AD 820 by Caliph al-Ma'mun's workmen using a battering ram.[38] The tunnel is cut straight through the masonry of the pyramid for approximately 27 metres (89 ft), then turns sharply left to encounter the blocking stones in the Ascending Passage. It is believed that their efforts dislodged the stone fitted in the ceiling of the Descending Passage to hide the entrance to the Ascending Passage and it was the noise of that stone falling and then sliding down the Descending Passage, which alerted them to the need to turn left. Unable to remove these stones, however, the workmen tunnelled up beside them through the softer limestone of the Pyramid until they reached the Ascending Passage. It is possible to enter the Descending Passage from this point, but access is usually forbidden.[39]

text: Pyramid complex

text: The Great Pyramid is surrounded by a complex of several buildings including small pyramids. The Pyramid Temple, which stood on the east side of the pyramid and measured 52.2 metres (171 ft) north to south and 40 metres (130 ft) east to west, has almost entirely disappeared apart from the black basalt paving. There are only a few remnants of the causeway which linked the pyramid with the valley and the Valley Temple. The Valley Temple is buried beneath the village of Nazlet el-Samman; basalt paving and limestone walls have been found but the site has not been excavated.[40][41] The basalt blocks show "clear evidence" of having been cut with some kind of saw with an estimated cutting blade of 15 feet (4.6 m) in length, capable of cutting at a rate of 1.5 inches (38 mm) per minute. John Romer suggests that this "super saw" may have had copper teeth and weighed up to 300 pounds (140 kg). He theorizes that such a saw could have been attached to a wooden trestle and possibly used in conjunction with vegetable oil, cutting sand, emery or pounded quartz to cut the blocks, which would have required the labour of at least a dozen men to operate it.[42]

text: On the south side are the subsidiary pyramids, popularly known as Queens' Pyramids. Three remain standing to nearly full height but the fourth was so ruined that its existence was not suspected until the recent discovery of the first course of stones and the remains of the capstone. Hidden beneath the paving around the pyramid was the tomb of Queen Hetepheres I, sister-wife of Sneferu and mother of Khufu. Discovered by accident by the Reisner expedition, the burial was intact, though the carefully sealed coffin proved to be empty.

text: The Giza pyramid complex, which includes among other structures the pyramids of Khufu, Khafre and Menkaure, is surrounded by a cyclopean stone wall, the Wall of the Crow. Mark Lehner has discovered a worker's town outside of the wall, otherwise known as "The Lost City", dated by pottery styles, seal impressions, and stratigraphy to have been constructed and occupied sometime during the reigns of Khafre (2520–2494 BC) and Menkaure (2490–2472 BC).[43][44] Recent discoveries by Mark Lehner and his team at the town and nearby, including what appears to have been a thriving port, suggest the town and associated living quarters consisting of barracks called "galleries" may not have been for the pyramid workers after all, but rather for the soldiers and sailors who utilized the port. In light of this new discovery, as to where then the pyramid workers may have lived Lehner now suggests the alternative possibility they may have camped on the ramps he believes were used to construct the pyramids or possibly at nearby quarries.[45]

text: In the early 1970s, the Australian archaeologist Karl Kromer excavated a mound in the South Field of the plateau. This mound contained artefacts including mudbrick seals of Khufu, which he identified with an artisans' settlement.[46] Mudbrick buildings just south of Khufu's Valley Temple contained mud sealings of Khufu and have been suggested to be a settlement serving the cult of Khufu after his death.[47] A worker's cemetery used at least between Khufu's reign and the end of the Fifth Dynasty was discovered south of the Wall of the Crow by Zahi Hawass in 1990.[48]

text: Boats

text: There are three boat-shaped pits around the pyramid, of a size and shape to have held complete boats, though so shallow that any superstructure, if there ever was one, must have been removed or disassembled. In May 1954, the Egyptian archaeologist Kamal el-Mallakh discovered a fourth pit, a long, narrow rectangle, still covered with slabs of stone weighing up to 15 tons. Inside were 1,224 pieces of wood, the longest 23 metres (75 ft) long, the shortest 10 centimetres (0.33 ft). These were entrusted to a boat builder, Haj Ahmed Yusuf, who worked out how the pieces fit together. The entire process, including conservation and straightening of the warped wood, took fourteen years.

text: The result is a cedar-wood boat 43.6 metres (143 ft) long, its timbers held together by ropes, which is currently housed in a special boat-shaped, air-conditioned museum beside the pyramid. During construction of this museum, which stands above the boat pit, a second sealed boat pit was discovered. It was deliberately left unopened until 2011 when excavation began on the boat.[49]

text: Looting

text: Although succeeding pyramids were smaller, pyramid building continued until the end of the Middle Kingdom. However, as authors Briar and Hobbs claim, "all the pyramids were robbed" by the New Kingdom, when the construction of royal tombs in a desert valley, now known as the Valley of the Kings, began.[50][51] Joyce Tyldesley states that the Great Pyramid itself "is known to have been opened and emptied by the Middle Kingdom", before the Arab caliph Abdullah al-Mamun entered the pyramid around AD 820.[38]

text: I. E. S. Edwards discusses Strabo's mention that the pyramid "a little way up one side has a stone that may be taken out, which being raised up there is a sloping passage to the foundations". Edwards suggested that the pyramid was entered by robbers after the end of the Old Kingdom and sealed and then reopened more than once until Strabo's door was added. He adds: "If this highly speculative surmise be correct, it is also necessary to assume either that the existence of the door was forgotten or that the entrance was again blocked with facing stones", in order to explain why al-Ma'mun could not find the entrance.[52]

text: He also discusses a story told by Herodotus. Herodotus visited Egypt in the 5th century BC and recounts a story that he was told concerning vaults under the pyramid built on an island where the body of Cheops lies. Edwards notes that the pyramid had "almost certainly been opened and its contents plundered long before the time of Herodotus" and that it might have been closed again during the Twenty-sixth Dynasty of Egypt when other monuments were restored. He suggests that the story told to Herodotus could have been the result of almost two centuries of telling and retelling by Pyramid guides.[53]


document_title: List of most-followed Instagram accounts

question_text: who has the most followers in the world on instagram

root

text: Top accounts[edit]

text: All-time[edit]

text: The following table lists the top 25 most followed accounts on Instagram, with each total rounded to the nearest million followers, as well as the profession of each user and country of origin.[1]

tag: p

text:
Rank
Chg
Account name
Owner
Followers
(millions)
Profession
Country

1.

@instagram
Instagram
231
Social media platform
 USA

2.

@selenagomez
Selena Gomez
132
Musician and actress

3.

@cristiano
Cristiano Ronaldo
119
Footballer
 POR

4.

@arianagrande
Ariana Grande
117
Musician and actress
 USA

5.

@beyonce
Beyoncé
110
Musician and actress

6.

@kimkardashian
Kim Kardashian
106
Reality TV personality

7.

@taylorswift
Taylor Swift
106
Musician and actress

8.

@kyliejenner
Kylie Jenner
100
Reality TV personality

9.

@therock
Dwayne Johnson
99
Actor and professional wrestler

10.

@justinbieber
Justin Bieber
96
Musician
 CAN

11.

@neymarjr
Neymar
88
Footballer
 BRA

12.

@kendalljenner
Kendall Jenner
86
Model
 USA

13.

@leomessi
Lionel Messi
86
Footballer
 ARG

14.

@nickiminaj
Nicki Minaj
85
Musician
 TRI

15.

@natgeo
National Geographic
85
Magazine
 USA

16.

@nike
Nike
75
Sportswear multinational corporation

17.

@mileycyrus
Miley Cyrus
73
Musician and actress

18.

@jlo
Jennifer Lopez
71
Musician and actress

19.

@khloekardashian
Khloé Kardashian
71
Reality TV personality

20.

@katyperry
Katy Perry
68
Musician

21.

@ddlovato
Demi Lovato
65
Musician and actress

22.

@kourtneykardash
Kourtney Kardashian
60
Reality TV personality

23.

@badgalriri
Rihanna
59
Musician
 BAR

24.

@victoriassecret
Victoria's Secret
58
Lingerie retailer
 USA

25.

@kevinhart4real
Kevin Hart
56
Comedian

As of January 21, 2018[update]

tag: table

text: By country[edit]

text:
Rank
Chg
Country
Account name
Owner
Followers
(millions)
Profession

1.

 United States
@instagram
Instagram
231
Social media platform

2.

 Portugal
@cristiano
Cristiano Ronaldo
119
Footballer

3.

 Canada
@justinbieber
Justin Bieber
96
Musician

4.

 Brazil
@neymarjr
Neymar
88
Footballer

5.

 Argentina
@leomessi
Lionel Messi
86
Footballer

6.

 Trinidad and Tobago
@nickiminaj
Nicki Minaj
85
Musician

7.

 Barbados
@badgalriri
Rihanna
59
Musician

8.

 Spain
@realmadrid
Real Madrid C.F.
55
Football club

9.

 Colombia
@shakira
Shakira
45
Musician

10.

 Hong Kong
@9gag
9GAG
44
Social media platform

11.

 United Kingdom
@davidbeckham
David Beckham
42
Model

12.

 Sweden
@iamzlatanibrahimovic
Zlatan Ibrahimović
30
Footballer

As of January 14, 2018[update]


document_title: Morse code

question_text: who used morse code in world war 2

question_tokens: who used morse code in world war 2

text: Morse code

text: Development and history

text: Beginning in 1836, the American artist Samuel F. B. Morse, the American physicist Joseph Henry, and Alfred Vail developed an electrical telegraph system. This system sent pulses of electric current along wires which controlled an electromagnet that was located at the receiving end of the telegraph system. A code was needed to transmit natural language using only these pulses, and the silence between them. Around 1837, Morse, therefore, developed an early forerunner to the modern International Morse code. Around the same time, Carl Friedrich Gauss and Wilhelm Eduard Weber (1833) as well as Carl August von Steinheil (1837) had already used codes with varying word lengths for their telegraphs. Since around 1800, European experimenters had been making progress with earlier battery-powered signaling systems in emitting oxygen and hydrogen bubbles through liquid, flipping magnetic semaphore flags, tripping alarms across long distances over wire, and other techniques. The numerous ingenious experimental encoding designs they devised and demonstrated were telegraphic precursors to practical applications.[2]

text: In 1837, William Cooke and Charles Wheatstone in England began using an electrical telegraph that also used electromagnets in its receivers. However, in contrast with any system of making sounds of clicks, their system used pointing needles that rotated above alphabetical charts to indicate the letters that were being sent. In 1841, Cooke and Wheatstone built a telegraph that printed the letters from a wheel of typefaces struck by a hammer. This machine was based on their 1840 telegraph and worked well; however, they failed to find customers for this system and only two examples were ever built.[3]

text: On the other hand, the three Americans' system for telegraphy, which was first used in about 1844, was designed to make indentations on a paper tape when electric currents were received. Morse's original telegraph receiver used a mechanical clockwork to move a paper tape. When an electrical current was received, an electromagnet engaged an armature that pushed a stylus onto the moving paper tape, making an indentation on the tape. When the current was interrupted, a spring retracted the stylus, and that portion of the moving tape remained unmarked.

text: The Morse code was developed so that operators could translate the indentations marked on the paper tape into text messages. In his earliest code, Morse had planned to transmit only numerals, and to use a codebook to look up each word according to the number which had been sent. However, the code was soon expanded by Alfred Vail in 1840 to include letters and special characters, so it could be used more generally. Vail estimated the frequency of use of letters in the English language by counting the movable type he found in the type-cases of a local newspaper in Morristown.[4] The shorter marks were called "dots", and the longer ones "dashes", and the letters most commonly used were assigned the shorter sequences of dots and dashes. This code was used since 1844 and became known as Morse landline code or American Morse code.

text: In the original Morse telegraphs, the receiver's armature made a clicking noise as it moved in and out of position to mark the paper tape. The telegraph operators soon learned that they could translate the clicks directly into dots and dashes, and write these down by hand, thus making the paper tape unnecessary. When Morse code was adapted to radio communication, the dots and dashes were sent as short and long tone pulses. It was later found that people become more proficient at receiving Morse code when it is taught as a language that is heard, instead of one read from a page.[5]

text: To reflect the sounds of Morse code receivers, the operators began to vocalize a dot as "dit", and a dash as "dah". Dots which are not the final element of a character became vocalized as "di". For example, the letter "c" was then vocalized as "dah-di-dah-dit".[6][7] Morse code was sometimes facetiously known as "iddy-umpty", and a dash as "umpty", leading to the word "umpteen".[8]

text: The Morse code, as it is used internationally today, was derived from a much refined proposal which became known as "Hamburg alphabet" by Friedrich Clemens Gerke in 1848. It was adopted by the Deutsch-Österreichischer Telegraphenverein (German-Austrian Telegraph Society) in 1851. This finally led to the International Morse code in 1865.

text: In the 1890s, Morse code began to be used extensively for early radio communication, before it was possible to transmit voice. In the late 19th and early 20th centuries, most high-speed international communication used Morse code on telegraph lines, undersea cables and radio circuits. In aviation, Morse code in radio systems started to be used on a regular basis in the 1920s. Although previous transmitters were bulky and the spark gap system of transmission was difficult to use, there had been some earlier attempts. In 1910, the US Navy experimented with sending Morse from an airplane.[9] That same year, a radio on the airship America had been instrumental in coordinating the rescue of its crew.[10] Zeppelin airships equipped with radio were used for bombing and naval scouting during World War I,[11] and ground-based radio direction finders were used for airship navigation.[11] Allied airships and military aircraft also made some use of radiotelegraphy. However, there was little aeronautical radio in general use during World War I, and in the 1920s, there was no radio system used by such important flights as that of Charles Lindbergh from New York to Paris in 1927. Once he and the Spirit of St. Louis were off the ground, Lindbergh was truly alone and incommunicado. On the other hand, when the first airplane flight was made from California to Australia in 1928 on the Southern Cross, one of its four crewmen was its radio operator who communicated with ground stations via radio telegraph.

text: Beginning in the 1930s, both civilian and military pilots were required to be able to use Morse code, both for use with early communications systems and for identification of navigational beacons which transmitted continuous two- or three-letter identifiers in Morse code. Aeronautical charts show the identifier of each navigational aid next to its location on the map.

text: Radiotelegraphy using Morse code was vital during World War II, especially in carrying messages between the warships and the naval bases of the belligerents. Long-range ship-to-ship communication was by radio telegraphy, using encrypted messages because the voice radio systems on ships then were quite limited in both their range and their security. Radiotelegraphy was also extensively used by warplanes, especially by long-range patrol planes that were sent out by those navies to scout for enemy warships, cargo ships, and troop ships.

text: In addition, rapidly moving armies in the field could not have fought effectively without radiotelegraphy because they moved more rapidly than telegraph and telephone lines could be erected. This was seen especially in the blitzkrieg offensives of the Nazi German Wehrmacht in Poland, Belgium, France (in 1940), the Soviet Union, and in North Africa; by the British Army in North Africa, Italy, and the Netherlands; and by the U.S. Army in France and Belgium (in 1944), and in southern Germany in 1945.

text: Morse code was used as an international standard for maritime distress until 1999 when it was replaced by the Global Maritime Distress Safety System. When the French Navy ceased using Morse code on January 31, 1997, the final message transmitted was "Calling all. This is our last cry before our eternal silence."[12] In the United States the final commercial Morse code transmission was on July 12, 1999, signing off with Samuel Morse's original 1844 message, "What hath God wrought", and the prosign "SK".[13]

text: As of 2015, the United States Air Force still trains ten people a year in Morse.[14] The United States Coast Guard has ceased all use of Morse code on the radio, and no longer monitors any radio frequencies for Morse code transmissions, including the international medium frequency (MF) distress frequency of 500 kHz.[15] However, the Federal Communications Commission still grants commercial radiotelegraph operator licenses to applicants who pass its code and written tests.[16] Licensees have reactivated the old California coastal Morse station KPH and regularly transmit from the site under either this Call sign or as KSM. Similarly, a few US Museum ship stations are operated by Morse enthusiasts.[17]

text: User proficiency

text: Morse code speed is measured in words per minute (wpm) or characters per minute (cpm). Characters have differing lengths because they contain differing numbers of dots and dashes. Consequently, words also have different lengths in terms of dot duration, even when they contain the same number of characters. For this reason, a standard word is helpful to measure operator transmission speed. "PARIS" and "CODEX" are two such standard words.[18] Operators skilled in Morse code can often understand ("copy") code in their heads at rates in excess of 40 wpm.

text: In addition to knowing, understanding, and being able to copy the standard written alpha-numeric and punctuation characters or symbols at high speeds, skilled high speed operators must also be fully knowledgeable of all of the special unwritten Morse code symbols for the standard Prosigns for Morse code and the meanings of these special procedural signals in standard Morse code communications protocol.

text: International contests in code copying are still occasionally held. In July 1939 at a contest in Asheville, North Carolina in the United States Ted R. McElroy set a still-standing record for Morse copying, 75.2 wpm.[19] William Pierpont N0HFF also notes that some operators may have passed 100 wpm.[19] By this time, they are "hearing" phrases and sentences rather than words. The fastest speed ever sent by a straight key was achieved in 1942 by Harry Turner W9YZE (d. 1992) who reached 35 wpm in a demonstration at a U.S. Army base. To accurately compare code copying speed records of different eras it is useful to keep in mind that different standard words (50 dot durations versus 60 dot durations) and different interword gaps (5 dot durations versus 7 dot durations) may have been used when determining such speed records. For example, speeds run with the CODEX standard word and the PARIS standard may differ by up to 20%.

text: Today among amateur operators there are several organizations that recognize high-speed code ability, one group consisting of those who can copy Morse at 60 wpm.[20] Also, Certificates of Code Proficiency are issued by several amateur radio societies, including the American Radio Relay League. Their basic award starts at 10 wpm with endorsements as high as 40 wpm, and are available to anyone who can copy the transmitted text. Members of the Boy Scouts of America may put a Morse interpreter's strip on their uniforms if they meet the standards for translating code at 5 wpm.

text: International Morse Code

text: Morse code has been in use for more than 160 years—longer than any other electrical coding system. What is called Morse code today is actually somewhat different from what was originally developed by Vail and Morse. The Modern International Morse code, or continental code, was created by Friedrich Clemens Gerke in 1848 and initially used for telegraphy between Hamburg and Cuxhaven in Germany. Gerke changed nearly half of the alphabet and all of the numerals, providing the foundation for the modern form of the code. After some minor changes, International Morse Code was standardized at the International Telegraphy Congress in 1865 in Paris and was later made the standard by the International Telecommunication Union (ITU). Morse's original code specification, largely limited to use in the United States and Canada, became known as American Morse code or railroad code. American Morse code is now seldom used except in historical re-enactments.

text: Aviation

text: In aviation, instrument pilots use radio navigation aids. To ensure that the stations the pilots are using are serviceable, the stations all transmit a short set of identification letters (usually a two-to-five-letter version of the station name) in Morse code. Station identification letters are shown on air navigation charts. For example, the VOR based at Manchester Airport in England is abbreviated as "MCT", and MCT in Morse code is transmitted on its radio frequency. In some countries, during periods of maintenance, the facility may radiate a T-E-S-T code (▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄) or the code may be removed which tells pilots and navigators that the station is unreliable. In Canada, the identification is removed entirely to signify the navigation aid is not to be used.[21][22] In the aviation service, Morse is typically sent at a very slow speed of about 5 words per minute. In the U.S., pilots do not actually have to know Morse to identify the transmitter because the dot/dash sequence is written out next to the transmitter's symbol on aeronautical charts. Some modern navigation receivers automatically translate the code into displayed letters.

text: Amateur radio

text: International Morse code today is most popular among amateur radio operators, in the mode commonly referred to as "continuous wave" or "CW". (This name was chosen to distinguish it from the damped wave emissions from spark transmitters, not because the transmission is continuous.) Other keying methods are available in radio telegraphy, such as frequency shift keying.

text: The original amateur radio operators used Morse code exclusively since voice-capable radio transmitters did not become commonly available until around 1920. Until 2003, the International Telecommunication Union mandated Morse code proficiency as part of the amateur radio licensing procedure worldwide. However, the World Radiocommunication Conference of 2003 made the Morse code requirement for amateur radio licensing optional.[24] Many countries subsequently removed the Morse requirement from their licence requirements.[25]

text: Until 1991, a demonstration of the ability to send and receive Morse code at a minimum of five words per minute (wpm) was required to receive an amateur radio license for use in the United States from the Federal Communications Commission. Demonstration of this ability was still required for the privilege to use the HF bands. Until 2000, proficiency at the 20 wpm level was required to receive the highest level of amateur license (Amateur Extra Class); effective April 15, 2000, the FCC reduced the Extra Class requirement to five wpm.[26] Finally, effective on February 23, 2007, the FCC eliminated the Morse code proficiency requirements from all amateur radio licenses.

text: While voice and data transmissions are limited to specific amateur radio bands under U.S. rules, Morse code is permitted on all amateur bands—LF, MF, HF, VHF, and UHF. In some countries, certain portions of the amateur radio bands are reserved for transmission of Morse code signals only.

text: The relatively limited speed at which Morse code can be sent led to the development of an extensive number of abbreviations to speed communication. These include prosigns, Q codes, and a set of Morse code abbreviations for typical message components. For example, CQ is broadcast to be interpreted as "seek you" (I'd like to converse with anyone who can hear my signal). OM (old man), YL (young lady) and XYL ("ex-YL" – wife) are common abbreviations. YL or OM is used by an operator when referring to the other operator, XYL or OM is used by an operator when referring to his or her spouse. QTH is "location" ("My QTH" is "My location"). The use of abbreviations for common terms permits conversation even when the operators speak different languages.

text: Although the traditional telegraph key (straight key) is still used by some amateurs, the use of mechanical semi-automatic keyers (known as "bugs") and of fully automatic electronic keyers is prevalent today. Software is also frequently employed to produce and decode Morse code radio signals.

text: Other uses

text: Through May 2013, the First, Second, and Third Class (commercial) Radiotelegraph Licenses using code tests based upon the CODEX standard word were still being issued in the United States by the Federal Communications Commission. The First Class license required 20 WPM code group and 25 WPM text code proficiency, the others 16 WPM code group test (five letter blocks sent as simulation of receiving encrypted text) and 20 WPM code text (plain language) test. It was also necessary to pass written tests on operating practice and electronics theory. A unique additional demand for the First Class was a requirement of a year of experience for operators of shipboard and coast stations using Morse. This allowed the holder to be chief operator on board a passenger ship. However, since 1999 the use of satellite and very high-frequency maritime communications systems (GMDSS) has made them obsolete. (By that point meeting experience requirement for the First was very difficult.) Currently, only one class of license, the Radiotelegraph Operator License, is issued. This is granted either when the tests are passed or as the Second and First are renewed and become this lifetime license. For new applicants, it requires passing a written examination on electronic theory and radiotelegraphy practices, as well as 16 WPM codegroup and 20 WPM text tests. However, the code exams are currently waived for holders of Amateur Extra Class licenses who obtained their operating privileges under the old 20 WPM test requirement.

text: Radio navigation aids such as VORs and NDBs for aeronautical use broadcast identifying information in the form of Morse Code, though many VOR stations now also provide voice identification.[27] Warships, including those of the U.S. Navy, have long used signal lamps to exchange messages in Morse code. Modern use continues, in part, as a way to communicate while maintaining radio silence.

text: ATIS (Automatic Transmitter Identification System) uses Morse code to identify uplink sources of analog satellite transmissions.

text: Applications for the general public

text: An important application is signalling for help through SOS, "▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄". This can be sent many ways: keying a radio on and off, flashing a mirror, toggling a flashlight, and similar methods. SOS is not three separate characters, rather, it is a prosign SOS, and is keyed without gaps between characters.[28]

text: Some Nokia mobile phones offer an option[citation needed] to alert the user of an incoming text message with the Morse tone "▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄" (representing SMS or Short Message Service). In addition, applications are now available for mobile phones that enable short messages to be input in Morse Code.[29]

text: Morse code as an assistive technology

text: Morse code has been employed as an assistive technology, helping people with a variety of disabilities to communicate. Morse can be sent by persons with severe motion disabilities, as long as they have some minimal motor control. An original solution to the problem that caretakers have to learn to decode has been an electronic typewriter with the codes written on the keys. Codes were sung by users; see the voice typewriter employing morse or votem, Newell and Nabarro, 1968.

text: Morse code can also be translated by computer and used in a speaking communication aid. In some cases, this means alternately blowing into and sucking on a plastic tube ("sip-and-puff" interface). An important advantage of Morse code over row column scanning is that once learned, it does not require looking at a display. Also, it appears faster than scanning.

text: People with severe motion disabilities in addition to sensory disabilities (e.g. people who are also deaf or blind) can receive Morse through a skin buzzer.[citation needed].

text: In one case reported in the radio amateur magazine QST,[30] an old shipboard radio operator who had a stroke and lost the ability to speak or write could communicate with his physician (a radio amateur) by blinking his eyes in Morse. Two examples of communication in intensive care units were also published in QST, [31] [32] Another example occurred in 1966 when prisoner of war Jeremiah Denton, brought on television by his North Vietnamese captors, Morse-blinked the word TORTURE. In these two cases, interpreters were available to understand those series of eye-blinks.

text: Representation, timing, and speeds

text:
A sample Morse code transmission

The text "Welcome to Wikipedia, the free encyclopedia that anyone can edit." sent as Morse code at 13 wpm.

Problems playing this file? See media help.

text:
Morse code A through Z

"A B C D E F G H I J K L M N O P Q R S T U V W X Y Z" in Morse code at 8 wpm.

Problems playing this file? See media help.

text: This section includes inline links to audio files. If you have trouble playing the files, see Wikipedia Media help.

text: International Morse code is composed of five elements:[1]

text:
short mark, dot or "dit" (▄▄▄▄): "dot duration" is one time unit long
longer mark, dash or "dah" (▄▄▄▄▄▄): three time units long
inter-element gap between the dots and dashes within a character: one dot duration or one unit long
short gap (between letters): three time units long
medium gap (between words): seven time units long

tag: ol

text: Transmission

text: Morse code can be transmitted in a number of ways: originally as electrical pulses along a telegraph wire, but also as an audio tone, a radio signal with short and long tones, or as a mechanical, audible, or visual signal (e.g. a flashing light) using devices like an Aldis lamp or a heliograph, a common flashlight, or even a car horn. Some mine rescues have used pulling on a rope - a short pull for a dot and a long pull for a dash.

text: Morse code is transmitted using just two states (on and off). Historians have called it the first digital code. An alternative interpretation given by Robin Boast is that Morse code is not digital since its codes are not fixed-length (in contrast to Baudot code).[33] Morse code may be represented as a binary code, and that is what telegraph operators do when transmitting messages. Working from the above ITU definition and further defining a bit as a dot time, a Morse code sequence may be made from a combination of the following five-bit strings:

text:
short mark, dot or "dit" (▄▄▄▄): 1
longer mark, dash or "dah" (▄▄▄▄▄▄): 111
intra-character gap (between the dots and dashes within a character): 0
short gap (between letters): 000
medium gap (between words): 0000000

text: Note that the marks and gaps alternate: dots and dashes are always separated by one of the gaps, and that the gaps are always separated by a dot or a dash.

text: Morse messages are generally transmitted by a hand-operated device such as a telegraph key, so there are variations introduced by the skill of the sender and receiver — more experienced operators can send and receive at faster speeds. In addition, individual operators differ slightly, for example, using slightly longer or shorter dashes or gaps, perhaps only for particular characters. This is called their "fist", and experienced operators can recognize specific individuals by it alone. A good operator who sends clearly and is easy to copy is said to have a "good fist". A "poor fist" is a characteristic of sloppy or hard to copy Morse code.

text: Cable code

text: The very long time constants of 19th and early 20th century submarine communications cables required a different form of Morse signalling. Instead of keying a voltage on and off for varying times, the dits and dahs were represented by two polarities of voltage impressed on the cable, for a uniform time.[34]

text: Timing

text: Below is an illustration of timing conventions. The phrase "MORSE CODE", in Morse code format, would normally be written something like this, where – represents dahs and · represents dits:

text: Next is the exact conventional timing for this phrase, with = representing "signal on", and . representing "signal off", each for the time length of exactly one dit:

text: Spoken representation

text: Morse code is often spoken or written with "dah" for dashes, "dit" for dots located at the end of a character, and "di" for dots located at the beginning or internally within the character. Thus, the following Morse code sequence:

text: is orally:

text: Dah-dah dah-dah-dah di-dah-dit di-di-dit dit, Dah-di-dah-dit dah-dah-dah dah-di-dit dit.

text: There is little point in learning to read written Morse as above; rather, the sounds of all of the letters and symbols need to be learned, for both sending and receiving.

text: Speed in words per minute

text: All Morse code elements depend on the dot length. A dash is the length of 3 dots, and spacings are specified in number of dot lengths. An unambiguous method of specifying the transmission speed is to specify the dot duration as, for example, 50 milliseconds.

text: Specifying the dot duration is, however, not the common practice. Usually, speeds are stated in words per minute. That introduces ambiguity because words have different numbers of characters, and characters have different dot lengths. It is not immediately clear how a specific word rate determines the dot duration in milliseconds.

text: Some method to standardize the transformation of a word rate to a dot duration is useful. A simple way to do this is to choose a dot duration that would send a typical word the desired number of times in one minute. If, for example, the operator wanted a character speed of 13 words per minute, the operator would choose a dot rate that would send the typical word 13 times in exactly one minute.

text: The typical word thus determines the dot length. It is common to assume that a word is 5 characters long. There are two common typical words: "PARIS" and "CODEX". PARIS mimics a word rate that is typical of natural language words and reflects the benefits of Morse code's shorter code durations for common characters such as "e" and "t". CODEX offers a word rate that is typical of 5-letter code groups (sequences of random letters). Using the word PARIS as a standard, the number of dot units is 50 and a simple calculation shows that the dot length at 20 words per minute is 60 milliseconds. Using the word CODEX with 60 dot units, the dot length at 20 words per minute is 50 milliseconds.

text: Because Morse code is usually sent by hand, it is unlikely that an operator could be that precise with the dot length, and the individual characteristics and preferences of the operators usually override the standards.

text: For commercial radiotelegraph licenses in the United States, the Federal Communications Commission specifies tests for Morse code proficiency in words per minute and in code groups per minute.[35] The Commission specifies that a word is 5 characters long. The Commission specifies Morse code test elements at 16 code groups per minute, 20 words per minute, 20 code groups per minute, and 25 words per minute.[36] The word per minute rate would be close to the PARIS standard, and the code groups per minute would be close to the CODEX standard.

text: While the Federal Communications Commission no longer requires Morse code for amateur radio licenses, the old requirements were similar to the requirements for commercial radiotelegraph licenses.[37]

text: A difference between amateur radio licenses and commercial radiotelegraph licenses is that commercial operators must be able to receive code groups of random characters along with plain language text. For each class of license, the code group speed requirement is slower than the plain language text requirement. For example, for the Radiotelegraph Operator License, the examinee must pass a 20 word per minute plain text test and a 16 word per minute code group test.[16]

text: Based upon a 50 dot duration standard word such as PARIS, the time for one dot duration or one unit can be computed by the formula:

text: Where: T is the unit time, or dot duration in milliseconds, and W is the speed in wpm.

text: High-speed telegraphy contests are held; according to the Guinness Book of Records in June 2005 at the International Amateur Radio Union's 6th World Championship in High Speed Telegraphy in Primorsko, Bulgaria, Andrei Bindasov of Belarus transmitted 230 morse code marks of mixed text in one minute.[38]

text: Farnsworth speed

text: Sometimes, especially while teaching Morse code, the timing rules above are changed so two different speeds are used: a character speed and a text speed. The character speed is how fast each individual letter is sent. The text speed is how fast the entire message is sent. For example, individual characters may be sent at a 13 words-per-minute rate, but the intercharacter and interword gaps may be lengthened so the word rate is only 5 words per minute.

text: Using different character and text speeds is, in fact, a common practice, and is used in the Farnsworth method of learning Morse code.

text: Alternative display of common characters in International Morse code

text: Some methods of teaching Morse code use a dichotomic search table.

text: Link budget issues

text: Morse Code cannot be treated as a classical radioteletype (RTTY) signal when it comes to calculating a link margin or a link budget for the simple reason of it possessing variable length dots and dashes as well as variant timing between letters and words. For the purposes of Information Theory and Channel Coding comparisons, the word PARIS is used to determine Morse Code's properties because it has an even number of dots and dashes.

text: Morse Code, when transmitted essentially, creates an AM signal (even in on/off keying mode), assumptions about signal can be made with respect to similarly timed RTTY signalling. Because Morse code transmissions employ an on-off keyed radio signal, it requires less complex transmission equipment than other forms of radio communication.

text: Morse code also requires less signal bandwidth than voice communication, typically 100–150 Hz, compared to the roughly 2400 Hz used by single-sideband voice, although at a lower data rate.

text: Morse code is usually heard at the receiver as a medium-pitched on/off audio tone (600–1000 Hz), so transmissions are easier to copy than voice through the noise on congested frequencies, and it can be used in very high noise / low signal environments. The transmitted power is concentrated into a limited bandwidth so narrow receiver filters can be used to suppress interference from adjacent frequencies. The audio tone is usually created by use of a beat frequency oscillator.

text: The narrow signal bandwidth also takes advantage of the natural aural selectivity of the human brain, further enhancing weak signal readability. This efficiency makes CW extremely useful for DX (distance) transmissions, as well as for low-power transmissions (commonly called "QRP operation", from the Q-code for "reduce power").

text: The ARRL has a readability standard for robot encoders called ARRL Farnsworth Spacing[39] that is supposed to have higher readability for both robot and human decoders. Some programs like WinMorse[40] have implemented the standard.

text: Learning methods

text: People learning Morse code using the Farnsworth method are taught to send and receive letters and other symbols at their full target speed, that is with normal relative timing of the dots, dashes, and spaces within each symbol for that speed. The Farnsworth method is named for Donald R. "Russ" Farnsworth, also known by his call sign, W6TTB. However, initially exaggerated spaces between symbols and words are used, to give "thinking time" to make the sound "shape" of the letters and symbols easier to learn. The spacing can then be reduced with practice and familiarity.

text: Another popular teaching method is the Koch method, named after German psychologist Ludwig Koch, which uses the full target speed from the outset but begins with just two characters. Once strings containing those two characters can be copied with 90% accuracy, an additional character is added, and so on until the full character set is mastered.

text: In North America, many thousands of individuals have increased their code recognition speed (after initial memorization of the characters) by listening to the regularly scheduled code practice transmissions broadcast by W1AW, the American Radio Relay League's headquarters station.[citation needed]

text: Mnemonics

text: Visual mnemonic charts have been devised over the ages. Baden-Powell included one in the Girl Guides handbook[41] in 1918.

text: In the United Kingdom, many people learned the Morse code by means of a series of words or phrases that have the same rhythm as a Morse character. For instance, "Q" in Morse is dah-dah-di-dah, which can be memorized by the phrase "God save the Queen", and the Morse for "F" is di-di-dah-dit, which can be memorized as "Did she like it."

text: A well-known Morse code rhythm from the Second World War period derives from Beethoven's Fifth Symphony, the opening phrase of which was regularly played at the beginning of BBC broadcasts. The timing of the notes corresponds to the Morse for "V", di-di-di-dah, understood as "V for Victory" (as well as the Roman numeral for the number five).[42][43]

text: Letters, numbers, punctuation, prosigns for Morse code and non-English variants

text:
Category
Character
Code

Letters
A, a

· −

Letters
B, b

− · · ·

Letters
C, c

− · − ·

Letters
D, d

− · ·

Letters
E, e

·

Letters
F, f

· · − ·

Letters
G, g

− − ·

Letters
H, h

· · · ·

Letters
I, i

· ·

Letters
J, j

· − − −

Letters
K, k

Prosign for "Invitation to transmit"

− · −

Letters
L, l

· − · ·

Letters
M, m

− −

Letters
N, n

− ·

Letters
O, o

− − −

Letters
P, p

· − − ·

Letters
Q, q

− − · −

Letters
R, r

· − ·

Letters
S, s

· · ·

Letters
T, t

−

Letters
U, u

· · −

Letters
V, v

· · · −

Letters
W, w

· − −

Letters
X, x

− · · −

Letters
Y, y

− · − −

Letters
Z, z

− − · ·

Numbers
0

− − − − −

Numbers
1

· − − − −

Numbers
2

· · − − −

Numbers
3

· · · − −

Numbers
4

· · · · −

Numbers
5

· · · · ·

Numbers
6

− · · · ·

Numbers
7

− − · · ·

Numbers
8

− − − · ·

Numbers
9

− − − − ·

Punctuation
Period [.]

· − · − · −

Punctuation
Comma [,]

− − · · − −

Punctuation
Question Mark [?]

· · − − · ·

Punctuation
Apostrophe [']

· − − − − ·

Punctuation
Exclamation Point [!]

KW digraph
Not in ITU-R recommendation

− · − · − −

Punctuation
Slash/Fraction Bar [/]

− · · − ·

Punctuation
Parenthesis (Open)

− · − − ·

Punctuation
Parenthesis (Close)

− · − − · −

Punctuation
Ampersand (or "Wait") [&]

AS digraph
Prosign for "Wait"
Not in ITU-R recommendation

· − · · ·

Punctuation
Colon [:]

− − − · · ·

Punctuation
Semicolon [;]

Not in ITU-R recommendation

− · − · − ·

Punctuation
Double Dash [=]

− · · · −

Punctuation
Plus sign [+]

· − · − ·

Punctuation
Hyphen, Minus Sign [-]

− · · · · −

Punctuation
Underscore [_]

Not in ITU-R recommendation

· · − − · −

Punctuation
Quotation mark ["]

· − · · − ·

Punctuation
Dollar sign [$]

SX digraph
Not in ITU-R recommendation

· · · − · · −

Punctuation
At Sign [@]

AC digraph

· − − · − ·

Prosigns
End of work

· · · − · −

Prosigns
Error

· · · · · · · ·

Prosigns
Invitation to Transmit

Also used for K

− · −

Prosigns
Starting Signal

− · − · −

Prosigns
New Page Signal

AR digraph
Message separator
Single-line display may use printed "+"

· − · − ·

Prosigns
Understood

Also used for Ŝ

· · · − ·

Prosigns
Wait

also used for Ampersand [&]

· − · · ·

Non-English extensions
À, à

Shared by À, Å

· − − · −

Non-English extensions
Ä, ä

Shared by Ä, Æ, Ą

· − · −

Non-English Extensions
Å, å

Shared by À, Å

· − − · −

Non-English extensions
Ą, ą

Shared by Ä, Æ, Ą

· − · −

Non-English extensions
Æ, æ

Shared by Ä, Æ, Ą

· − · −

Non-English extensions
Ć, ć

Shared by Ć, Ĉ, Ç

− · − · ·

Non-English extensions
Ĉ, ĉ

Shared by Ć, Ĉ, Ç

− · − · ·

Non-English Extensions
Ç, ç

Shared by Ć, Ĉ, Ç

− · − · ·

Non-English extensions
CH, ch

Shared by CH, Ĥ, Š

− − − −

Non-English extensions
Đ, đ

Shared by Đ, É, Ę
Not to be confused with Eth (Ð, ð)
(É is the only accented character included in ITU-R recommendation)

· · − · ·

Non-English extensions
Ð, ð

Not to be confused with D with stroke (Đ, đ)

· · − − ·

Non-English extensions
É, é

Shared by Đ, É, Ę
(É is the only accented character included in ITU-R recommendation)

· · − · ·

Non-English extensions
È, è

Shared by È, Ł

· − · · −

Non-English extensions
Ę, ę

Shared by Đ, É, Ę
(É is the only accented character included in ITU-R recommendation)

· · − · ·

Non-English extensions
Ĝ, ĝ

− − · − ·

Non-English extensions
Ĥ, ĥ

Shared by CH, Ĥ, Š

− − − −

Non-English extensions
Ĵ, ĵ

· − − − ·

Non-English extensions
Ł, ł

Shared by È, Ł

· − · · −

Non-English extensions
Ń, ń

Shared by Ń, Ñ

− − · − −

Non-English extensions
Ñ, ñ

Shared by Ń, Ñ

− − · − −

Non-English extensions
Ó, ó

Shared by Ó, Ö, Ø

− − − ·

Non-English extensions
Ö, ö

Shared by Ó, Ö, Ø

− − − ·

Non-English extensions
Ø, ø

Shared by Ó, Ö, Ø

− − − ·

Non-English extensions
Ś, ś

· · · − · · ·

Non-English extensions
Ŝ, ŝ

Prosign for "Understood"

· · · − ·

Non-English extensions
Š, š

Shared by CH, Ĥ, Š

− − − −

Non-English extensions
Þ, þ

· − − · ·

Non-English extensions
Ü, ü

Shared by Ü, Ŭ

· · − −

Non-English extensions
Ŭ, ŭ

Shared by Ü, Ŭ

· · − −

Non-English extensions
Ź, ź

− − · · − ·

Non-English extensions
Ż, ż

− − · · −

text: Prosigns

text: Prosigns for Morse code are special (usually) unwritten procedural signals or symbols that are used to indicate changes in communications protocol status or white space text formatting actions.

text: Symbol representations

text: The symbols !, $ and & are not defined inside the ITU recommendation on Morse code, but conventions for them exist. The @ symbol was formally added in 2004.

text: There is no standard representation for the exclamation mark (!), although the KW digraph (▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄) was proposed in the 1980s by the Heathkit Company (a vendor of assembly kits for amateur radio equipment).

text: While Morse code translation software prefers the Heathkit version, on-air use is not yet universal as some amateur radio operators in North America and the Caribbean continue to prefer the older MN digraph (▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄) carried over from American landline telegraphy code.

text:
The ITU has never codified formal Morse Code representations for currencies as the ISO 4217 Currency Codes are preferred for transmission.
The $ sign code was represented in the Phillips Code, a huge collection of abbreviations used on land line telegraphy, as SX.

tag: ul

text: The representation of the & sign given above, often shown as AS, is also the Morse prosign for wait. In addition, the American landline representation of an ampersand was similar to "ES" (▄▄▄▄▄▄▄▄▄▄▄▄) and hams have carried over this usage as a synonym for "and" (WX HR COLD ES RAINY, "the weather here is cold & rainy").

text:
On May 24, 2004 — the 160th anniversary of the first public Morse telegraph transmission — the Radiocommunication Bureau of the International Telecommunication Union (ITU-R) formally added the @ ("commercial at" or "commat") character to the official Morse character set, using the sequence denoted by the AC digraph (▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄).
This sequence was reportedly chosen to represent "A[T] C[OMMERCIAL]" or a letter "a" inside a swirl represented by a "C".[44] The new character facilitates sending email addresses by Morse code and is notable since it is the first official addition to the Morse set of characters since World War I.

text: Non-Latin extensions

text: For Chinese, Chinese telegraph code is used to map Chinese characters to four-digit codes and send these digits out using standard Morse code. Korean Morse code uses the SKATS mapping, originally developed to allow Korean to be typed on western typewriters. SKATS maps hangul characters to arbitrary letters of the Latin script and has no relationship to pronunciation in Korean. For Russian and Bulgarian, Russian Morse code is used to map the Cyrillic characters to four-element codes. Many of the characters are encoded the same way (A, O, E, I, T, M, N, R, K, etc.). Bulgarian alphabet contains 30 characters, which exactly match all possible combinations of 1, 2, 3, and 4 dots and dashes. Russian requires 1 extra character, "Ы" which is encoded with 5 elements.

text: Unusual variants

text: During early World War I (1914–1916), Germany briefly experimented with 'dotty' and 'dashy' Morse, in essence adding a dot or a dash at the end of each Morse symbol. Each one was quickly broken by Allied SIGINT, and standard Morse was restored by Spring 1916. Only a small percentage of Western Front (North Atlantic and Mediterranean Sea) traffic was in 'dotty' or 'dashy' Morse during the entire war. In popular culture, this is mostly remembered in the book The Codebreakers by Kahn and in the national archives of the UK and Australia (whose SIGINT operators copied most of this Morse variant). Kahn's cited sources come from the popular press and wireless magazines of the time.[45]

text: Other forms of 'Fractional Morse' or 'Fractionated Morse' have emerged.[46]

text: Decoding software

text: Decoding software for Morse code ranges from software-defined wide-band radio receivers coupled to the Reverse Beacon Network,[47] which decodes signals and detects CQ messages on ham bands, to smartphone applications.[48]


document_title: Pemberley

question_text: where is pemberley filmed in pride and prejudice

text: Pemberley

text: This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. (September 2010) (Learn how and when to remove this template message)

text: Pemberley is the fictional country estate owned by Fitzwilliam Darcy, the male protagonist in Jane Austen's novel Pride and Prejudice. It is located near the fictional town of Lambton, and believed by some to be based on Chatsworth House,[1] near Bakewell in Derbyshire.

text: In describing the estate, Austen uses uncharacteristically explicit symbolism to represent the geographical home of the man at the centre of the novel. On first visiting the estate, Elizabeth Bennet is charmed by the beauty of the surrounding countryside, as indeed she is by Mr. Darcy himself. Elizabeth had already rejected Mr. Darcy's first proposal by the time she visits Pemberley—it is his letter, the praise of his housekeeper, and his own courteous behaviour at Pemberley that bring about a change in her opinion of Mr. Darcy.

text: In Pride and Prejudice[edit]

text: They gradually ascended for half a mile, and then found themselves at the top of a considerable eminence, where the wood ceased, and the eye was instantly caught by Pemberley House, situated on the opposite side of a valley, into which the road with some abruptness wound. It was a large, handsome, stone building, standing well on rising ground, and backed by a ridge of high woody hills;—and in front, a stream of some natural importance was swelled into greater, but without any artificial appearance. Its banks were neither formal, nor falsely adorned. Elizabeth was delighted. She had never seen a place where nature had done more, or where natural beauty had been so little counteracted by an awkward taste. They were all of them warm in their admiration; and at that moment she felt that to be mistress of Pemberley might be something![2] Jane Austen (1813).

text: In other media[edit]

text:
Renishaw Hall, Derbyshire, England, UK was the setting for Pemberley in the 1980 BBC adaptation of Pride and Prejudice starring Elizabeth Garvie and David Rintoul, adapted from the novel by Fay Weldon.
Lyme Park, near Stockport, was the setting for Pemberley for the 1995 television series of Pride and Prejudice starring Jennifer Ehle and Colin Firth.
Chatsworth House, the original inspiration for Pemberley, was used for the exterior scenes for Joe Wright's 2005 film version of Pride and Prejudice starring Keira Knightley and Matthew Macfadyen. However, Wilton House was used for many of the interior scenes, such as those featuring Georgiana Darcy. Jane Austen mentions Chatsworth in the novel as one of the great houses Elizabeth and her aunt and uncle visited before Pemberley during their visit north. The Duchess of Devonshire believes that the author was thinking of Chatsworth House when describing Pemberley due to the great number of similarities between Chatsworth and Pemberley.[citation needed] Chatsworth was again used for exterior, and some interior, scenes for the BBC adaptation of Death Comes to Pemberley.[3]
Harewood House, near Leeds in West Yorkshire, was the setting for Pemberley in the ITV fantasy series Lost in Austen. This series was not a direct adaptation of the novel, but the novel provided the majority of the plots, characters and inspiration. Some interior scenes in the BBC adaptation of Death Comes to Pemberley were filmed at Harewood.
Pemberley Press is the name of the publishing house that Bridget Jones works at in the 2001 film Bridget Jones's Diary, in homage to Pride and Prejudice.
In The Lizzie Bennet Diaries, a vlog-style modern adaptation of Pride and Prejudice, Pemberley Digital is the name of Darcy's company. Darcy says Pemberley is the name of the place that his father's family comes from in England.

text:
Renishaw Hall as Pemberley in the 1980 TV serial

Lyme Park as Pemberley in the 1995 TV serial

Chatsworth House as Pemberley in the 2005 film

Harewood House as Pemberley in Lost in Austen