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70-450: Strowger, an undertaker , was motivated to invent an automatic telephone exchange after having difficulties with his telephone service. He became convinced that the manual telephone exchange operators were deliberately interfering with his calls, leading to loss of business. According to the local Bell Telephone Company manager Herman Ritterhoff, Strowger swore to "get even" with the telephone operators and "put every last one of them out of

140-404: A telephone keypad to leave messages on dealers' pagers . They are also retained for authenticity in historic properties such as the U.S. Route 66 Blue Swallow Motel , which date back to the era of named exchanges and pulse dialing. For dialing a digit of the telephone number, the user inserts a finger into the corresponding finger hole and rotates the dial clockwise until the finger reaches

210-407: A digit, the wheel is rotated against spring tension with one finger positioned in the corresponding hole, pulling the wheel with the finger to a stop position given by a mechanical barrier, the finger stop. When released at the finger stop, the wheel returns to its home position driven by the spring at a speed regulated by a governor device . During this return rotation, an electrical switch interrupts

280-519: A governor on the forward movement of the wheel, which proved to be difficult to operate correctly. Despite their lack of modern features, rotary dials occasionally find special uses, particularly in industrial equipment. For instance, the anti-drug Fairlawn Coalition of the Anacostia section of Washington, D.C., persuaded the phone company to reinstall rotary-dial pay phones in the 1980s to discourage loitering by drug purchasers, since they lacked

350-411: A job." Ritterhoff claimed that the real cause of Strowger's difficulties was a metal sign hung on his wall over his telephone, causing an intermittent short circuit when blown by the wind. Strowger conceived his invention in 1888, and was awarded a patent for an automatic telephone exchange in 1891. The initial model was made from a round collar box and some straight pins. While Almon Strowger devised

420-543: A legal requirement. The role of a funeral director in Canada can include embalming, sales, oversight of funeral services as well as other aspects of needed funeral services. A funeral director in Canada will assume many responsibilities after proper education and licensing. Courses will include science and biology, ethics, and practical techniques of embalming. There are a number of organizations available to Canadian funeral directors. Rotary dial A rotary dial

490-743: A mesh arrangement. This became quadratically more complex as each new customer was added, as each new customer needed a switch to connect to every other customer. In modern terminology, the previous systems were not " scalable ". From 1912, the British General Post Office , which also operated the British telephone system, installed several automatic telephone exchanges from several vendors in trials at Darlington on 10 October 1914 and Dudley on 9 September 1916 ( rotary system ), Fleetwood (relay exchange from Sweden), Grimsby (Siemens), Hereford (Lorimer) and Leeds (Strowger). The GPO selected

560-476: A preparation room for embalming, a chapel , and a casket selection room. They usually have a hearse for transportation of bodies, a flower car , and limousines . They also normally sell caskets and urns . Licensing requirements in the US are determined at the state level. Most require a combination of post-secondary education (typically an associate's degree ), passage of a National Board Examination, passage of

630-448: A state board examination, and one to two years' work as an apprentice . A funeral director in the UK will usually take on most of the administrative duties and arrangement of the funeral service, including flower arrangements, meeting with family members, and overseeing the funeral and burial service. Embalming or cremation of the body requires further training. In the UK no formal licence

700-411: A telephone dial in 1891. Before 1891, numerous competing inventions, and 26 patents for dials, push-buttons, and similar mechanisms, specified methods of signalling a destination telephone station that a subscriber wanted to call. Most inventions involved costly, intricate mechanisms and required the user to perform complex manipulations. The first commercial installation of a telephone dial accompanied

770-402: A telephone network, often by a line-finder which searches "backward" for the calling line; so requiring only a few relays (in most cases two, a Line, and a Cut-off relay), for the equipment required for each customer line. Later Strowger (SXS) exchanges often use a subscriber uniselector as part of the line equipment individual to each line, which searches "forward" for a first selector. This

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840-450: A telephone number. When calling the subscriber number 163, for example, the user had to push the hundreds button once, followed by six presses of the tens button, and three presses of the units button. In 1896, this system was supplanted by an automatic contact-making machine , or calling device . Further development continued during the 1890s and the early 1900s in conjunction with improvements in switching technology. Almon Brown Strowger

910-424: A telephone set for dialing. Each key requires a separate wire to the exchange. The keys are tapped to step the switch in two stages. The first set of incoming pulses raises the armature of an electromagnet to move a shaft which selects the desired level of contacts, by engaging a pawl with the upper ratchet. Another pawl, pivoting on the frame, holds the shaft at that height as it rotates. The second set of pulses, from

980-409: A term that was then perceived to have been tarnished by its association with death. The term mortician was the winning entry. People's need to respect the dead and their survivors is as ancient as civilization itself, and death care is among the world's oldest professions. Ancient Egypt is a probable pioneer in supporting full-time morticians; intentional mummification began around 2600 BC, with

1050-420: Is 10 bits per second, though the system will usually accept from about 9 through 13 pulses per second, a requirement due to variations in the rotary dial mechanism governor speed. This dialing method is the world's first mass scale digital addressing system. It is sometimes erroneously referred to as an analog system due to some individuals' beliefs that mechanical and old are synonyms for analog . However, like

1120-406: Is a component of a telephone or a telephone switchboard that implements a signaling technology in telecommunications known as pulse dialing . It is used when initiating a telephone call to transmit the destination telephone number to a telephone exchange . On the rotary dial, the digits are arranged in a circular layout, with one finger hole in the finger wheel for each digit. For dialing

1190-402: Is controlled by the current pulses coming from the originating customer's telegraph keys, and later from the rotary dial. The Strowger switch has three banks of contacts. Toward the upper end of each shaft are two ratchets . The upper one has ten grooves, and raises the shaft. The lower one has long vertical teeth (on the other side, hidden). The Strowger switch uses two telegraph-type keys on

1260-400: Is defined by the type of dial system in use. The encoding has traditionally varied by country, or by the manufacturer of the telephone system. For example, Sweden used one pulse to signal the number zero, and ten pulses to signal the number nine. In Finland , where many telephones were of Swedish manufacture, one pulse signaled digit 1 , and ten pulses 0 . New Zealand used ten pulses minus

1330-507: Is more economical for higher calling-rate domestic or business customers, and has the advantage that access to additional switches can readily be added if the traffic increases (the number of linefinders serving a group is limited by the wiring multiple installed). Hence exchanges with subscriber uniselectors were usually used at British exchanges with a high proportion of business customers, e.g. director exchanges, or in New Zealand where

1400-602: Is required to become an undertaker (funeral director). There are national trade organizations such as the British Institute of Funeral Directors (BIFD), the National Association of Funeral Directors (NAFD) and the Society of Allied and Independent Funeral Directors (SAIF). The BIFD offers a licence to funeral directors who have obtained a diploma-level qualification; these diplomas are offered by both

1470-786: The Automatic Electric Company , which Strowger was involved in founding, although Strowger himself seems not to have been involved in further developments. The Strowger patents were exclusively licensed to the Automatic Electric Company. Strowger sold his patents in 1896 for US$ 1,800 (equivalent to $ 57,000 in 2023) and sold his share in Automatic Electric in 1898 for $ 10,000 (equivalent to $ 310,000 in 2023). His patents subsequently sold for $ 2,500,000 (equivalent to $ 48,000,000 in 2023) in 1916. Company engineers continued development of

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1540-408: The "cascading" enabled connection to many more customers, and to customers at other exchanges. Another requirement for commercial systems was a circuit to detect a busy connection (line) and return a busy signal to the calling subscriber. Instead of dedicating an expensive first-stage selector switch to each customer as in the first exchange, the customer was given access to the first-stage switch of

1610-529: The BIFD and NAFD. The British Institute of Embalmers (BIE) offers embalming training and qualifications. All of the national organizations offer voluntary membership of "best practice" standards schemes, which includes regular premises inspection and adherence to a specific code of conduct . These organizations help funeral directors demonstrate that they are committed to continuing professional development , and they have no issue with regulation should it become

1680-564: The DC to pass even if the line polarity were reversed. In case of line polarity reversal, the LED would not light, but the phone would work anyway. The LED and Zener diode were contained in the same package for ease of assembly in manufacturing. In the United Kingdom the letter "O" was combined with the digit "0" rather than "6". In large cities the seven-digit numbers comprised three letters for

1750-604: The Operator was already free, and the cam that removed the shunt on the line when the dial was rotated to the "0" position could be altered to include the adjacent digit "9" (and "8" if required) so that calls to "0" and "999" could be made without inserting coins. In New Zealand, 111 was selected because New Zealand reverse-numbered dials make each digit "1" send 9 pulses to the central office/telephone exchange (like "9" in Britain), allowing British exchange equipment to be used off

1820-554: The Strowger designs and submitted several patents in the names of its employees. The Strowger system was widely used until the development of the more reliable crossbar switch , an electromechanical switch with a matrix of vertical and horizontal bars and simpler motions. Strowger's patent specifies dialing equipment at the customer location and the switching equipment at the central office. The telegraph keys or telephone dial creates trains of on-off current pulses corresponding to

1890-460: The Strowger switches for small and medium-sized cities and towns. The selection of switching systems for London and other large cities was not decided until the 1920s, when the Director telephone system was adopted. The Director systems used SXS switches for destination routing and number translation facilities similar to the register used in common-control exchanges. Using similar equipment as in

1960-533: The US were owned by one of three corporations. The majority of morticians work in small, independent family-run funeral homes. The owner usually hires two or three other morticians to help them. Often, this hired help is in the family, perpetuating the family's ownership. Other firms that were family-owned have been acquired and are operated by large corporations such as Service Corporation International , though such homes usually trade under their pre-acquisition names. Most funeral homes have one or more viewing rooms,

2030-416: The best-preserved mummies dating to around 1570 to 1075 BC. Specialized priests spent 70 full days on a single corpse. Only royalty, nobility and wealthy commoners could afford the service, considered by some to be essential for accessing eternal life; the poorer performed very basic intentional mummification or simply buried the body in a dry spot hoping it would naturally mummify. In every case, an intact body

2100-468: The central exchange. Each key had to be tapped the correct number of times to step the switch and make the desired connection. To connect to number 1256, the user would press the first key once, the second key twice, the third key five times and the final key six times. The company installed and opened the first commercial exchange in his then-home town of La Porte, Indiana on November 3, 1892. The exchange had around 75 subscribers. The installation followed

2170-518: The combination pattern of letters assigned to each digit, which became the standard in North America. Large cities like New York City would ultimately require a seven-digit telephone number. Some tests in the early 1900s indicated that the short-term memory span of many people was insufficient for seven digits, causing dialing errors (the documentation for these tests is lost). As large cities had both manual and automatic exchanges for many years,

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2240-473: The corpse for the purpose of enhancing its appearance) with the proper licenses. A funeral director may work at a funeral home or be an independent employee. The term mortician is derived from the Latin word mort- ('death') with the ending -ician . In 1895, the trade magazine The Embalmers' Monthly put out a call for a new name for the profession in the US to distance itself from the title undertaker ,

2310-465: The dead for the benefit of the living arose in the European Age of Enlightenment . Dutch scientist Frederik Ruysch 's work attracted the attention of royalty and legitimized postmortem anatomy . Most importantly, Ruysch developed injected substances and waxes that could penetrate the smallest vessels of the body and seal them against decay. Historically, from ancient Egypt to Greece and Rome to

2380-417: The dead, as well as the arrangements for the funeral ceremony (although not the directing and conducting of the funeral itself unless clergy are not present). Funeral directors may at times be asked to perform tasks such as dressing (in garments usually suitable for daily wear), casketing (placing the corpse in the coffin), and cossetting (applying any sort of cosmetic or substance to the best viewable areas of

2450-473: The dial impulse pulses and the red LED shows the dial's off-normal contact function. Off-normal contacts typically serve two additional functions. They may implement a shunt across the transmitter circuit and induction coil to maximize the pulsing signal of the dial by eliminating all internal impedances of the telephone set. Another function is to short-circuit or interrupt the telephone receiver during dialing, to prevent audible clicking noise from being heard by

2520-508: The dial in the handset. In Spain , such phones were manufactured for CTNE ( Compañía Telefónica Nacional de España ) by Málaga -based factory "CITESA", being named as "Góndola" phones by its particular shape. Spanish Góndola sets were fitted from the beginning with a red LED series connected with the line, allowing the dial ("disco" in Spanish) to be backlit while dialling. For that, the LED was bridged by an anti-parallel Zener diode , to allow

2590-409: The dial turned toward the finger stop position. When the user's hand motion was erratic, it could produce the wrong digit. In the late 19th century, the dial was refined to operate automatically by a recoil spring. The user selected the digit to be dialed, rotated the dial to the finger stop, then released it. The spring caused the dial to rotate back to its home position during which time constant speed

2660-445: The dial was released, the weights moved outward, pulling the ends of their springs together. Springs were fixed to a collar on the shaft at one end and to the hub of a sliding brake disc at the other end. At speed, the brake disc contacted a friction pad. This governor was similar to that in spring-driven windup phonograph turntables of the early 20th century. Both types had wrap-spring clutches for driving their governors. When winding

2730-500: The dial-return spring, these clutches disconnected to let the dial turn quickly. When the dial was released, the clutch spring wrapped tightly to drive the governor. While winding the dial, a spring-centered pawl in the Western Electric dial wiggled off-center when driven by the cam on the dial shaft. Teeth on that cam were spaced apart by the same angle as dial hole spacing. During winding, the pawl moved off-center away from

2800-433: The digit, i.e. how far the dial had to travel to return to the rest position. A rotary dial typically features a circular construction. The shaft that actuates the mechanical switching mechanism is driven by the finger wheel, a disk that has ten finger holes aligned close to the circumference. The finger wheel may be transparent or opaque permitting the viewing of the face plate (number plate), either in whole, or only showing

2870-435: The digits 1–9, and 0 (which sends 10 pulses). This equipment originally consisted of two telegraph keys engaged by knife switches , and evolved into the rotary dial telephone. The central office switching equipment has a two-motion stepping switch . A contact arm is moved up to select one of ten rows of contacts, and then rotated clockwise to select one of ten contacts in that row, a total of 100 choices. The stepping motion

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2940-580: The digits from 1 through 0 respectively) was also used for a short period in the Soviet Union in the 1950s and 1960s, but by the next decade this practice was largely discontinued. Letter codes were not used in all East European countries. A relic of these differences is found in emergency telephone numbers used in various countries; the United Kingdom selected 999 due to the ease of converting call office dials to make free calls. "0" for

3010-491: The direct current (DC) of the telephone line ( local loop ) the specific number of times associated with each digit and thereby generates electrical pulses which the telephone exchange decodes into each dialed digit. Thus, each of the ten digits is encoded in sequences to correspond to the number of pulses; thus, the method is sometimes called decadic dialing . Pulse count dialing is a digital addressing system which uses decimal pulse count modulation. The typical average baud rate

3080-518: The early United States, women typically did all of the preparation of dead bodies. They were called "layers out of the dead". In the mid-19th century, gender roles within funeral service in the United States began to change. In the late 19th century, the industry became male dominated with the development of funeral directors, which changed the funeral industry both locally and nationally. In 2003, 15 percent of corporately owned funeral homes in

3150-426: The exchange name, followed by four numbers. Before 1960 Australian rotary dial telephones had each number's corresponding letter printed on a paper disc in the centre of the plate, with space where the subscriber could add the phone number. The paper was protected by a clear plastic disc, held in place by a form of retaining ring which also served to locate the disc radially. The Australian letter-to-number mapping

3220-433: The finger stop. The user then releases the finger wheel by pulling the finger from the hole. A spring around the dial shaft rotates it back to the rest position. During the period of return, the dial operates electrical contacts that break the electrical continuity of the local loop, and interrupt the current flow a certain number of times for each digit marked on the front of the dial. The number of pulses sent for each digit

3290-465: The first commercial installation of a 99-line automatic telephone exchange in La Porte, Indiana , in 1892, which was based on the 1891 Strowger designs. The original dials required complex operational sequences. A workable, albeit error-prone, system was invented by the Automatic Electric Company using three push-buttons on the telephone. These buttons represented the hundreds, tens, and single units of

3360-418: The gear drove the worm. The worm, highly polished, had extreme pitch, with teeth at about 45° to its axis. This was the same as the gearing for the speed-limiting fan in traditional music boxes. The Western Electric governor was a cup surrounding spring-loaded pivoted weights with friction pads. The Automatic Electric governor had weights on the middle of curved springs made from strip stock. When it sped up after

3430-525: The independent telephone companies, rotary dial service in the Bell System in the United States was not common until the early 1920s. From the 1960s onward, the rotary dial was gradually supplanted by push-button telephones , first introduced to the public at the 1962 World's Fair under the trade name Touch-Tone (DTMF). Touch-tone technology primarily used a keypad in the form of a rectangular array of push-buttons. Although no longer in common use,

3500-449: The initial concept, he was not alone in his endeavors and sought the assistance of his brother Arnold, nephew William, and others with a knowledge of electricity and financing to realize the concept. The Strowger Automatic Telephone Exchange Company was founded in 1891. In the original design patent, four keys were added near the telephone, one each for thousands, hundreds, tens and units, with each key having an additional wire connection to

3570-573: The largest manufacturers, that of the Western Electric Company for the Bell System, and that of the Automatic Electric Company . The Western Electric dial had spur gears to power the governor, so the axis of the governor was parallel to the dial shaft. The Automatic Electric governor shaft was parallel to the plane of the dial at a right angle to the dial shaft. The governor shaft had worm gearing in which, very atypically,

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3640-417: The normally-closed pulsing contacts. When the dial was released, the cam teeth moved the pawl the other way to open and release the dial contacts. In the Automatic Electric dial, the pulsing cam and governor were driven by a wrap-spring clutch as the dial returned. When winding, that clutch disconnected both cam and governor. Early dials worked by direct or forward rotating action. The pulses were generated as

3710-460: The number assignment for each finger hole. The faceplate is printed with digits, and often letters, corresponding to each finger hole. Digit 1 is typically set in the upper right quadrant of the dial front, then the numbers progress counterclockwise. A curved device, the finger stop is positioned in the lower right quadrant. Some dialing mechanism allowed the use of physical locking mechanisms to prevent unauthorized use. The lock could be integral to

3780-530: The number desired; so dialing the digit 7 produces three pulses. In Norway , the North American system with the digit 1 corresponding to one pulse was used, except for the capital city, Oslo , which used the same "inverse" system as in New Zealand. The sequencing of the digits on the dial varies accordingly. Rotary dials have no redial feature; the entire telephone number must be dialed for every attempted call. The time it took for dialing depended on

3850-537: The numbers for manual or automatic exchanges used the same format, which could be either spoken or dialed. In the late 1940s, telephones were redesigned with the numbers and letters displayed on a ring outside the finger wheel to provide better visibility. Even after the transition to DTMF dialing with push-button keypads in most areas, pulse-dialing telephones continued to be produced for some time, even with keypads for dialing, for use with certain private exchange systems. Some of these can be distinguished visually by

3920-414: The original patented design, with four keys and four additional line wires connected to the exchange, but not all of the keys were used. Early advertising called the new invention the "girl-less, cuss-less, out-of-order-less, wait-less telephone". In 1896 the company patented the finger-wheel dial as an improvement to the existing four-key design. The Strowger Automatic Telephone Exchange Company became

3990-433: The presence of the funeral procession by wailing loudly. Other paid actors would don the masks of ancestors and recreate their personalities, dramatizing the exploits of their departed scion. These purely ceremonial undertakers of the day nonetheless had great religious and societal impact; a larger number of actors indicated greater power and wealth for the deceased and their family. Modern ideas about proper preservation of

4060-438: The provision of local free calling meant that residential customers had a relatively high calling rate. The fundamental modularity of the system combined with its step-by-step (hence the alternative name) selection process and an almost unlimited potential for expansion gives the Strowger system its technical advantage. Previous systems had all been designed for a fixed number of subscribers to be switched directly to each other in

4130-493: The rest of the network was deemed beneficial and the equipment could be manufactured in Britain. Funeral director A funeral director , also known as an undertaker or mortician ( American English ), is a professional who has licenses in funeral arranging and embalming (or preparation of the deceased) involved in the business of funeral rites. These tasks often entail the embalming and burial or cremation of

4200-436: The rotary dial's legacy remains in the verb "to dial (a telephone number)". From as early as 1836 onward, various suggestions and inventions of dials for sending telegraph signals were reported. After the first commercial telephone exchange was installed in 1878, the need for an automated, user-controlled method of directing a telephone call became apparent. Addressing the technical shortcomings, Almon Brown Strowger invented

4270-409: The second key, operates another electromagnet. Its pawl engages the (hidden) vertical teeth in the lower ratchet to rotate the shaft to the required position. It is kept there against spring tension by a pawl pivoted on the frame. When the switch returns to its home position, typically when a call is complete, a release magnet disengages the pawls that hold the shaft in position. An interlock ensures that

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4340-584: The shelf. In addition to the ten digits, the faceplate is often printed with letters corresponding to each position. In North America, traditional dials have letter codes displayed with the numbers under the finger holes in the following pattern: 1, 2 ABC, 3 DEF, 4 GHI, 5 JKL, 6 MNO, 7 PRS, 8 TUV, 9 WXY, and 0 (sometimes Z) Operator. Letters were associated with the dial numbers to represent telephone exchange names in communities that required multiple central offices. For example, "RE7-3456" represented "REgent 7-3456". In 1917, W. G. Blauvelt of AT&T developed

4410-518: The spring on the shaft rotates it to angular home position before it drops to its home position by gravity. The commercial version of the Strowger switch, as developed by the Strowger Automatic Telephone Exchange Company, used a rotary dial for signalling to the exchange. The original final selector (connector) switch which connected to 100 customers was supplemented by preceding group selector stages, as

4480-450: The telegraph, which is also mechanical and digital, and which uses both pulse count and pulse width modulation for communicating, pulse dialing is a digital communication method used for addressing telephone subscribers. The first patent for a rotary dial was granted to Almon Brown Strowger on November 29, 1892, but the commonly known form with holes in the finger wheel was not introduced until about 1904. While used in telephone systems of

4550-417: The telephone itself or a separate device inserted through the finger hole nearest the finger stop to prevent the dial from rotating. The rotational return speed of the dial to its rest position is controlled by the governor , a mechanical regulating device, that assures a constant electrical pulsing rate of the dial. In the United States, two principal dial mechanisms arose in the engineering laboratories of

4620-406: The telephone user. Some telephones include a small dial built into the handset, with a movable finger stop. The user rotates the dial clockwise until the finger stop ceases moving, then releases both. In this design the holes extend around the full circumference of the dial, allowing a reduced diameter. This was introduced by Western Electric on the compact Trimline telephone , the first to locate

4690-407: Was A=1, B=2, F=3, J=4, L=5, M=6, U=7, W=8, X=9, Y=0, so the phone number BX 3701 was in fact 29 3701. When Australia around 1960 changed to all-numeric telephone dials, a mnemonic to help people associate letters with numbers was the sentence, "All Big Fish Jump Like Mad Under Water eXcept Yabbies ." Alphabetic designation of exchanges with Cyrillic letters (А, Б, В, Г, Д, Е, Ж, И, К, Л for each of

4760-546: Was considered paramount to access the afterlife. Across successive cultures, religion remained a prime motive for securing a body against decay and/or arranging burial in a planned manner; some considered the fate of departed souls to be fixed and unchangeable (e.g. ancient Mesopotamia) and considered care for a grave to be more important than the actual burial. In ancient Rome , wealthy individuals trusted family to care for their corpse, but funeral rites would feature professional mourners: most often actresses who would announce

4830-403: Was maintained with a centrifugal governor . Dials at user stations typically produced pulses at the rate of ten pulses per second (PPS), while dials on operator consoles on crossbar or electronic exchanges often pulsed at 18 PPS. The rotary dial governor is subject to wear and aging, and may require periodic cleaning, lubrication and adjustment by a technician. In the video, the green LED shows

4900-417: Was the first to file a patent for a rotary dial on December 21, 1891, which was awarded on November 29, 1892, as U.S. patent 486,909 . The early rotary dials used lugs on a finger plate instead of holes, and did not produce a linear sequence of pulses, but interrupted two independent circuits for control of relays in the exchange switch. The pulse train was generated without the control of spring action or

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