环球雅思入学测试题(7)

2020-12-14 00:12

allowed Annie Ellsworth, the young daughter of a friend, to choose the words of the message, and she selected a verse from Numbers XXIII, 23:―What hath God wrought?‖ which was recorded onto paper tape. Morse’s early system produced a paper copy with raised dots and dashes, which were translated later by and operator,

Painting: Self Portrait by Samuel Morse -- Inventor of the Telegraph

Samuel Morse and his associates obtained private funds to extend their line to Philadelphia and New York .Small telegraph companies, meanwhile began functioning in the East, South, and Midwest. Dispatching trains by telegraph started in 1851, the same year Western Union began business. Western Union built its first transcontinental telegraph line in 1861, mainly along rights-of-way.

In 1881, the Postal Telegraph System entered the field for economic reasons, and merged with Western Union in 1943.

The original Morse telegraph printed code on tape. However, in the United States the operation developed into sending by key and receiving by ear. A trained Morse operator could transmit 40 to 50 words per minute. Automatic transmission, introduced in 1914, handled more than twice that number.

In 1913 Western Union developed multiplexing, which made it possible to transmit eight messages simultaneously over a single wire (four in each direction) Teleprinter machines came into use about 1925. Varioplex, introduced in 1936, enabled a single wire to carry 72 transmissions at the same time (36 in each direction). Two years later Western Union introduced the first of its automatic facsimile devices. In 1959 Western Union inaugurated TELEX which enables subscribers to the teleprinter service to dial each other directly.

Until 1877, all rapid long-distance communication depended upon the telegraph. That year, a rival technology developed that would again change the face of communication ----the telephone. By 1879, patent litigation between Western Union and the infant telephone system was ended in an agreement that largely separated the two services.

Samuel Morse is best known as the inventor of the telegraph, but he is also esteemed for his contributions to American portraiture. His painting is characterized by delicate technique and vigorous honesty and insight into the character of his subjects.

Questions 13-20

Complete the table below using the in formation in Reading Passage .

Choose your answers (A---M) from the box below the table and write them in boxes 13-20 on your answer sheet.


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