The word is still sometimes employed in this sense, as of the ship's telegraph, by means of which orders are mechanically transmitted from the navigating bridge to the engine room, but when used without qualification it usually denotes telegraphic apparatus worked by electricity, whether the signals that express the words of the message are visual, auditory or written.
- Although the history of practical electric telegraphy does not date much further back than the middle of the, 9th century, the idea of using electricity for telegraphic purposes is much older.
The application of this to telegraphic purposes was suggested by Laplace and taken up by Ampere, and afterwards by Triboaillet and by Schilling, whose work forms the foundation of much of modern telegraphy.
The first requisite for electro-telegraphic communication between two localities is an insulated conductor extending from one to the other.
Copper is not yet universally employed, price being the governing factor in its employment; moreover, the conducting quality of the iron used for telegraphic purposes has of late years been very greatly improved.
Bristol, Exeter and other important towns have been laid, and eventually telegraphic communication between every important town in the United Kingdom will be rendered safe from interruptions caused by gales or snowstorms.
This was followed by various other cables between England and the neighbouring countries, and their success naturally revived the idea which had been suggested in 1845 of establishing telegraphic communication between England and America, though this enterprise, on account of the distance and the greater depth of water, was of a much more formidable character.
Visiting England in 1856, Field entered into an agreement with Bright and with John Watkins Brett, who with his brother Jacob had proposed the constructing of an Atlantic cable eleven years previously, with the object of forming a company for establishing and working electric telegraphic communication between Newfoundland and Ireland.
In 1868 the International Bureau of Telegraphic Administrations was constituted at Berne, and a convention was formulated by which a central office was appointed to collect and publish information and generally to promote the interests of international telegraphy.
His Life of his father (1898), his Address to London Chamber of Commerce on " Imperial Telegraphic Communication " (1902), Lecture to Royal United Service Institution on " Submarine Telegraphy " (1907), Lectures to Royal Naval War College (1910) and R.E.
Assoc. Report), when he drew attention to the considerable distance over which inductive effects occurred between parallel wires forming portions of telephonic and telegraphic circuits.
In series with the tube is placed a single voltaic cell and a telegraphic relay, and Marconi added certain coils placed across the spark contacts of the relay to prevent the local sparks affecting the coherer.
With this apparatus some of Marconi's earliest successes, such as telegraphing across the English Channel, were achieved, and telegraphic communication at the rate of fifteen words or so a minute established between the East Goodwin lightship and the South Foreland lighthouse, also between the Isle of Wight and the Lizard in Cornwall.
When electric waves fell on the antenna they caused the mercury-steel junction to become conductive during the time they endured, and the siphon recorder therefore to write signals consisting of short or long deflexions of its pen and therefore notches of various length on the ink line drawn on the strip of telegraphic tape.
12039 of 1896) brought forward the idea of focusing a beam of electric radiation for telegraphic purposes on a distant station by means of parabolic mirrors, and tried this method successfully on Salisbury Plain up to a distance of about a couple of miles.
Successes achieved in those provinces failed, however, to save Nicotera from the wrath of the Chamber, and on the 14th of December 1877 a cabinet crisis arose over a question concerning the secrecy of telegraphic correspondence.
Since 1890 further and more rigorous application of the telegraphic method of determining longitudes differentially with Greenwich has resulted in a slight correction (amounting to about 2" of arc) to the previous determination by the same method through Suez.
But it is futile to seek the effect of much dealing in " futures " in the differences between price movements in the various markets, because (I) demand expresses itself in different ways-in Germany, for example, spinners buy to hold large stocks-and (2) the markets are in telegraphic communication, so that their price movements are kept parallel.
There is an extensive telegraphic system linking the towns of the province to one another, and, through the surrounding countries, with Europe and the rest of the world.
There is a direct telegraphic service to Gondokoro and Khartum and to Mombasa.
The colonial revenue is chiefly derived from customs, stamp duties, land tax, income tax, beer excise, postal and telegraphic services, railways, and crown land sales and rents.
There are complete postal and telegraphic facilities in all parts of the colony save the Saharan Territories, and cable communication with France.
The postal and telegraphic services are also somewhat inadequate.
Guatemala joined the Postal Union in 1881; but its postal and telegraphic services have suffered greatly from financial difficulties.
There are no roads in the province, and very little internal communication and trade; but a wireless telegraphic system has been installed in communication with Rhodes: and there is a landline from Bengazi to Tripoli.
Even people who know her fairly well have written in the magazines about Miss Sullivan's "mysterious telegraphic communications" with her pupil.