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Acoustic telegraph
(gcide) | Acoustic \A*cous"tic\ (#; 277), a. [F. acoustique, Gr. ?
relating to hearing, fr. ? to hear.]
Pertaining to the sense of hearing, the organs of hearing, or
the science of sounds; auditory.
[1913 Webster]
Acoustic duct, the auditory duct, or external passage of
the ear.
Acoustic telegraph, a telegraph making audible signals; a
telephone.
Acoustic vessels, brazen tubes or vessels, shaped like a
bell, used in ancient theaters to propel the voices of the
actors, so as to render them audible to a great distance.
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Acoustic telegraph
(gcide) | Telegraph \Tel"e*graph\, n. [Gr. ? far, far off (cf. Lith. toli)
+ -graph: cf. F. t['e]l['e]graphe. See Graphic.]
An apparatus, or a process, for communicating intelligence
rapidly between distant points, especially by means of
preconcerted visible or audible signals representing words or
ideas, or by means of words and signs, transmitted by
electrical action.
[1913 Webster]
Note: The instruments used are classed as indicator,
type-printing, symbol-printing, or chemical-printing
telegraphs, according as the intelligence is given by
the movements of a pointer or indicator, as in Cooke &
Wheatstone's (the form commonly used in England), or by
impressing, on a fillet of paper, letters from types,
as in House's and Hughe's, or dots and marks from a
sharp point moved by a magnet, as in Morse's, or
symbols produced by electro-chemical action, as in
Bain's. In the offices in the United States the
recording instrument is now little used, the receiving
operator reading by ear the combinations of long and
short intervals of sound produced by the armature of an
electro-magnet as it is put in motion by the opening
and breaking of the circuit, which motion, in
registering instruments, traces upon a ribbon of paper
the lines and dots used to represent the letters of the
alphabet. See Illustration in Appendix, and {Morse
code}.
[1913 Webster]
Note: In 1837, Samuel F. B. Morse, an American artist,
devised a working electric telegraph, based on a rough
knowledge of electrical circuits, electromagnetic
induction coils, and a scheme to encode alphabetic
letters. He and his collaborators and backers
campaigned for years before persuading the federal
government to fund a demonstration. Finally, on May 24,
1844, they sent the first official long-distance
telegraphic message in Morse code, "What hath God
wrought," through a copper wire strung between
Washington, D.C., to Baltimore, Maryland. The phrase
was taken from the Bible, Numbers 23:23. It had been
suggested to Morse by Annie Ellworth, the young
daughter of a friend. --Library of Congress, American
Memories series
(http://memory.loc.gov/ammem/today/may24.html).
[PJC]
Acoustic telegraph. See under Acoustic.
Dial telegraph, a telegraph in which letters of the
alphabet and numbers or other symbols are placed upon the
border of a circular dial plate at each station, the
apparatus being so arranged that the needle or index of
the dial at the receiving station accurately copies the
movements of that at the sending station.
Electric telegraph, or Electro-magnetic telegraph, a
telegraph in which an operator at one station causes words
or signs to be made at another by means of a current of
electricity, generated by a battery and transmitted over
an intervening wire.
Facsimile telegraph. See under Facsimile.
Indicator telegraph. See under Indicator.
Pan-telegraph, an electric telegraph by means of which a
drawing or writing, as an autographic message, may be
exactly reproduced at a distant station.
Printing telegraph, an electric telegraph which
automatically prints the message as it is received at a
distant station, in letters, not signs.
Signal telegraph, a telegraph in which preconcerted
signals, made by a machine, or otherwise, at one station,
are seen or heard and interpreted at another; a semaphore.
Submarine telegraph cable, a telegraph cable laid under
water to connect stations separated by a body of water.
Telegraph cable, a telegraphic cable consisting of several
conducting wires, inclosed by an insulating and protecting
material, so as to bring the wires into compact compass
for use on poles, or to form a strong cable impervious to
water, to be laid under ground, as in a town or city, or
under water, as in the ocean.
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