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the corresponding note is faintly audible. To intensify the effect the line current, in practice, is simply passed to earth through the "primary," P, of an induction-coil, and the more intense secondary current is used. In the figure, B is a hollow wooden resonance-box, with a bulging zinc face, b. This box is carried by a metal axle, A, supported by a stand, s: it is rotated by turning the handle, E. The zinc face is connected by a wire, w, to the axle; h is merely an air-hole in the face of the box. One end of the "secondary coil," s, is connected by wire to the metal axle at the terminal a ; the other end is connected to a bare wire held in the operator's hand, as shown. The operator lightly presses a finger of this hand on the zinc face, while with the other he rotates the box, and the dry rasp of the skin on the zinc surface is changed into a musical note whenever the current passes.

Like M. la Cour, Gray also provides that the vibratory current shall close a local circuit and record the message in permanent marks, by means of a Morse or other recording instrument. For this purpose he employs a receiver similar to the string-transmitter shown in Fig. 14. The line current, passing through the magnets of this instrument, sets the tense bar in vibration against the upper contact c, thus closing the local circuit and actuating the local recorder.

Mr. Gray's apparatus is now successfully operated over more than 2400 miles of the Western Union Telegraph Company's lines, including distances of several hundred miles. As many as four, and even eight, messages are simultaneously sent. Both he and M. la Cour are still engaged in perfecting their apparatus, and we may reasonably expect that the telephone will ere long do good service as a practical telegraph.

b. The Articulating Telephone.

This ingenious little instrument is the most wonderful of all the forms of telephone, and the latest, as it is the greatest, to use the words of Sir William Thomson, "of all the marvels of the electric telegraph." Its peculiar faculty lies in the transmission of promiscuous sounds. Not only does it convey the blended notes of musical instruments, but it actually reproduces the human speech. It is easy to see how an instrument like this will become practically useful. For domestic or commercial purposes, for reports of lectures and speeches it is especially fit. It has the advantage of quickness over ordinary methods of telegraphing.

In these, each letter of a word is on an average composed of three distinct signals; but in the articulating telephone a whole word is transmitted by the single act of uttering it.

Mr. A. Graham Bell, the inventor of this now-famous instrument, is, we believe, a native of Edinburgh, and is now a Professor of Boston University, and a naturalised

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citizen of the United States. In December last he patented it in England.

The articulating telephone consists of two distinct apparatus, a sender and a receiver. Fig. 17 represents the sender, and Fig. 18 the receiver: they are both exceedingly simple. In the sender, м м are two coils of insulated wire

surrounding the two poles of a powerful permanent magnet. These coils are connected up together, and to the terminals tt, on the mahogany stand s. Immediately in front of the poles of a magnet is a membrane stretched on a ring, R. This membrane carries an oblong piece of soft iron cemented to it just opposite the poles of the magnet. A suitable acoustic cavity, or mouthpiece to speak into, o, fitted with three screws for tightening up the membrane, complete the apparatus. The sender speaks into the mouthpiece in an elevated voice, and the membrane, vibrating in unison, carries the piece of soft iron-which is really a movable armature-to and from the poles of the magnet. This has the effect of inducing a magneto-electric current in the coils of wire, MM, which are connected up to the line. The strength of this induced current varies continuously," as nearly as may be, in simple proportion to the velocity of a particle of air engaged in constituting the sound." It travels along the line, and passes through the receiver at the distant station, evoking there the sounds which gave

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rise to it. The receiver is even more simple than the sender, and its action is the reverse. It consists of a tubular electromagnet, m, encased in iron to concentrate its power as much as possible on the circular disk armature, a, which is so fixed as to be free to vibrate over its cavity. It is connected up in circuit with the line by the terminals shown. The induced current coming from the sending station passes through the coil of this electro-magnet, and sets the thin disk armature into sonorous vibrations, which are distinctly and clearly heard as a reproduction of the original sounds.

In his address to the physical section of the British Association at Glasgow last year, Sir William Thomson thus

related his personal experience of this speaking telegraph at the Centennial Exhibition, Philadelphia. "In the Canadian department I heard To be, or not to be there's the rub,' through an electric wire; but scorning monosyllables, the electric articulation rose to higher flights, and gave me passages taken at random from the New York newspapers: S.s. Cox has arrived' (I failed to make out the s.s. Cox); 'The City of New York,' 'Senator Morton,' 'The Senate has resolved to print a thousand extra copies,' 'The Americans in London have resolved to celebrate the coming Fourth of July.' All this my own ears heard spoken to me with unmistakeable distinctness by the then circular disc armature of just such another little electromagnet as this I hold in my hand." Since then, Professor Bell has been perfecting his apparatus, and we find, on the authority of the "Scientific American," that he has recently achieved even more remarkable success. At a lecture which he delivered at Salem, Mass., a reporter of the "Boston Daily Globe" sent a verbal report of the lecture to the office of his paper in Boston, eighteen miles distant, by means of the telephone. Those reciving the message at Boston even heard, from time to time, the applause of the audience attending the lecture. From the platform Professor Bell spoke to his associate Mr. Watson in Boston. The latter then sent a telegraph message in musical notes, and also a tune from an organ, which were distinctly audible to the audience. On being asked for a song, Mr. Watson complied with "Auld Lang Syne," and finally made a speech, the words of which were heard by all present in the hall, as the applause testified. Mr. Watson then returned thanks, and the meeting ended, we are told, by those at Salem joining in the national anthem, "Hail, Columbia," with those at Boston. In view of these striking facts, it is hardly going too far to anticipate the time when, from St. James's Hall as a centre, Mr. Gladstone will be able to speak to the ears of the whole nation, collected at a hundred different towns, on Bulgarian atrocities, or some other topic of burning interest. Nor need we despair of seeing Herr Wagner from his throne at Bayreuth, dispensing the "music of the future" in one monstre concert to St. Petersburg, Vienna, London, New York-in short, to all the musical world at once.

V. ON THE PRESENT CONDITION OF CHILE.

HOUGH Chile has only had a settled Government for some twenty-five years, the country has now been autonomous for about half a century, and it will, therefore, not be uninteresting at the present time to consider briefly the results which have been achieved in that limited period. With this end in view we propose in this paper to abridge some notes from an exhaustive report, recently furnished to the Foreign Office by Her Majesty's Secretary of Legation at Santiago de Chile, on the progress and general condition of the Republic-a report which reflects great credit on its writer, and, apart from a few defects in the arrangement of its details, is one of the most complete that we remember to have met with in a long experience of such like documents.

We need not dwell at great length on Mr. Rumbold's introductory remarks on the geographical position and physical configuration of the country, for they are more or less familiar to all; but we may mention that Chile claims to extend from the 24th degree of southern latitude to Cape Horn, with a coast-line ranging over 2000 miles, the greater part of her territory-from the province of Aconcagua southwards-being describable as one broad valley running due north and south, with narrower lateral and intersecting valleys, each of which rises step-like above the other to the foot of the giant wall of the Andes. However genial the climate and fertile the soil, the extent of land available for cultivation is necessarily limited by the large proportion of hills and rocks, and by the extensive desert tracts of the northern districts. At the same time the natural declivity from the mountain to the ocean, distinctive of the whole country, as well as its inconsiderable breadth (nowhere much exceeding 120 miles), greatly facilitate communication with the coast at all points. It is thus marked out by Nature for easy exportation of its own produce, and is equally convenient of access to the sea-borne produce of other nations. The Chileans would therefore seem destined to become both an important agricultural and an important commercial and maritime community-points of resemblance with ourselves which they no doubt include in their claim to be considered "the English of South America." Mr. Rumbold does not

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