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a succession of shocks, that this apparent difficulty is over

come.

Thus, for example, a single shock may represent A; two shocks B; and three shocks C,-the number of shocks corresponding to the place which the letter occupies in the alphabet. This is the simplest, though not the most expeditious, mode of communicating intelligence by means of the Electric Telegraph, the messages being spelled, letter for letter, at one end of the wire, and read off at the other; and though, as we shall soon see, this method is not the most rapid, it is admirable for its simplicity, and sufficiently quick in its operations, when we bear in mind that, so far as distance is concerned, time is actually annihilated. It matters therefore very little whether five minutes, or ten, or even twenty, are occupied in transmitting a message over a space that could not be traversed by the swiftest locomotive in as many hours.

The other method, and that most generally employed, consists of a different management of the index, which instead of travelling, as in the other case, through the whole circuit of the alphabet, makes much fewer movements-seldom, we believe, exceeding five or six. Every one at all conversant with the properties of Electricity or Magnetism, knows that it exists in two states, called positive and negative, and possesses the double property of attracting or repelling. A familiar illustration of this fact is furnished by the little Dutch toys called magic swans, which, placed in water, are attracted or repulsed alternately as each end of the magnet is turned towards them. This principle will explain how an index can be moved to the right or left, at pleasure, by means of an electric or magnetic current, although placed hundreds of miles distant from the spot where the shock is first given. We will suppose, then, that a dial-plate like that of a clock or watch, without the numerals, and furnished with two or

more hands (for the number either of dials or hands can be multiplied if necessary) is placed at Glasgow, or Hull, or any other locality to which a message is to be sent. The party in London, whose business it is to transmit the intelligence, imparts one, two, or more, shocks to the wire, and the index at Glasgow or Hull is moved either to the right or left, the same number of times.

Thus, we will suppose the required letter to be A. A single movement to the right is forthwith given; if B be wanted, two movements in the same direction are made; and for C, three perhaps, of the same kind. For D, a single movement to the left would answer the purpose; for E, two; and for F, three. For G, one movement to the right, and one to the left, would do; for H, two of each, and for I, three. We have thus proceeded through more than a third part of the alphabet, in no case employing more than six shocks; and by multiplying the indices, or some other mode which it is not necessary to explain, all the letters may be thus transmitted. We do not pretend that this is actually the identical plan adopted by most of our railways, but it will furnish a sufficiently correct idea as to the way in which time may be economized, when compared with the plan first-mentioned, and which we are now about to describe.

Our engraving shows a dial-plate, around which the letters of the alphabet are arranged in order, having an index like the hand of a clock (pointing in this instance to the letter Y). After notice has been given by passing a shock along the wire, which rings a little bell crowning the apparatus; this index is adjusted to the point between Z and A, distinguished by a perpendicular line, and the signal having been returned, operations are commenced. Let us suppose the tidings to be communicated are these"O'BRIEN IS TAKEN." Shock after shock is given, and the index moves on, halting at those characters which

are printed in bolder type, till they are taken down at the other end, thus :—

ABCDEFGHIJKLMNOPQRSTUVW X Y Z X A B C D E F G H I J K L M N O P Q RSTUVWXYZ + ABCDEFGHIJKL

MNOPQRSTUVWXYZ + ABCDEFG

HIJKLMNOPQRSTUVWXYZX AB CDEFGHIJKLMNOPQRSTUVWXY ABCDEFGHIJKLMNOPQRSTU

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[ocr errors]

V W XZ+

ABCDEFGHIJKLM N O P Q

R S T U V W X Y Z + ABCDEFGHIJKL M N O P Q R S T U V W X Y Z X

It will thus be seen that there is a comparatively extravagant expenditure of time and trouble; more than twohundred movements being made for the sake of conveying a message that consists of but seventeen characters including stops. But when it is remembered that these movements are made about as fast as those of the seconds' hand upon a time-piece, it becomes clear that the whole transaction would not occupy more than four or five minutes, which spread over a distance of as many hundred miles, is really not worth consideration.

To simplify this method of passing a message, the party working the telegraph has merely to use a key-board, or to turn round a horizontal wheel by means of small pegs radiating from it, and distinguished by the several letters of the alphabet. Each of these pegs or cogs, in passing a certain point, communicates a shock to the wire, which causes the index at the other end to start forward in a similar manner, marking the self-same letters on the dial, as are at that moment under the eye of the operator.

Our engraving represents a farther improvement on this wonderful instrument, by means of which a message is not merely passed, but actually printed, the cogs on the wheel immediately behind the dial-plate being in fact so many

printing types, which press, in the required order, against the scroll of paper passing over the roller to the right. The following description conveys a very interesting account of this invention.

"It consists of a framework containing one or more type-wheels, the said type-wheels having on their circumferences, corresponding letters, words, or signs. Confining our description to one wheel, we observe that it is released from a state of rest, or checked in its revolution, by means of the electric circuit being either made or broken by an operator stationed at the key-board at the other or distant terminus, and the instant a key representing any particular letter, word, or sign is pressed down by the person at the key-board at one end of the line of telegraph, the corresponding letter, word, or sign of the type-wheel is printed, when a signal-bell rings giving notice of the fact at the other end of the line of telegraph, and this is repeated continuously without limit as to distance. The communications are printed on paper supplied from a scroll of unlimited length, from which any portion of the corres pondence may be cut off at pleasure. A slight electric power is sufficient to regulate the motion of the whole, the machinery being so adjusted that simple weight movements give rotation to the type-wheel and paper cylinder, and the same power also acts upon the escapement and signal bells.

"There is, however, another power on which much depends for certainty in printing the intended letters or signs; that is, the hydraulic or pneumatic regulator, which is so constructed that it is acted upon by the revolution of the type-wheel preventing the paper cylinder from being put into contact with any other of the letters of the typewheel than such as are required to be printed. The piston of the said hydraulic regulator being acted on by means of a catch and slot in a cam-wheel, in combination with ar

eccentric arbor and lever, each revolution of which causes the paper or the paper cylinder to be forcibly struck against the said type-wheel, and to be again as immediately released, a space being at the same instant made for the next letter, word, or sign by the paper cylinder having traversed the required distance."

THE LIVING RILL.

In the history of Emmeline Loveday, the narrator loses sight of every scene through which the reader has been before conducted. Whether he will enter others as pleasing as those which he has left, cannot be known until it is tried; but we must follow where we are led by our Living Rill, still hoping that we shall meet with lovely flowers, and trees of pleasant shadow and fragrant blossom, all along its borders.

The death of little Barbara occurred just before the commencement of the present century, and nothing is known of the history of Emmeline after that event, till she is found very early in the autumn, just come to reside with her aunt in the city of Bath.

Emmeline was the daughter of a captain in the royal navy, who, on the death of his lady, had left his child with his sister, Mrs. Lutterell, a widow of high Bath ton, residing in the Royal Crescent, whose character may be thus shortly summed up: She was a clever and consistent woman of the world, and no exception to the scripture assertion, that "the children of this world are wiser in their generation than the children of light." Worldly persons may understand what she was about when she kept her niece out of sight till it was the customary time to introduce her: as to other readers they will do as well without comprehending it. When it is added that Captain Loveday had not been at home for several years, and was expected to return soon, enough has been said to explain the condition of the family when Emmeline returned to live with her aunt, who it must be admitted, had never cultivated her affections.

Whoever has resided any time in the beautiful city of Bath, cannot fail to have admired the Royal Crescent, with its

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