circuit and battery, M the helices of the register magnet included in the circuit, which, as the standards, SS, are metallic, is broken only at the points ab. Now, the least possible space between these points effectually interrupts the current, and as they are covered with platinum, a very slight contact is sufficient to establish the connexion. The little instrument is so delicately adjustable, that often, when the breath would stop the vibrations of the lever, the circuit is broken and closed with certainty and regularity; this is also shown on a larger scale in fig. 28."

Many forms of this instrument have been devised, some with the levers vertical; in others, the magnet was attached at one end, and the style at the other end of a shaft working through a horizontal tube.

The figure (28) slightly amended, from one in the Phrenological Journal, March, 1851, represents the whole combination of the registering apparatus and its connexions with the main and local circuits, together with the distant and local operating keys. The register occupies the centre of the picture, being supported on two standards: T is a spool carrying a roll of paper; this paper is prepared by manufacturers for this especial use, by winding it into large rolls, and dividing it into smaller rolls of one inch or more in width by a knife, while it is revolving in a lathe; from this spool the paper is drawn between the two rollers x and y, which are turned by means of the weight U, moving the clock work above it; D is the register magnet, E the lever, having the armature at L, and its axis or fulcrum to the left of it, also at the extreme left, the style playing in a groove of the lower surface of the wheel y; S on the right, is a screw to limit the motion of the style, a distance of one-eighth of an inch being usually allowed; it also contains a spiral spring below, to separate the armature and magnet; the paper is dealt off steadily from the spool, and a momentum is prevented by springs fixed on the axis of the spool between the latter and its standards; formerly a break was suspended from the lower surface of the lever upon some of the clock wheels below, to permit and arrest their motion, but this is now supplied by the small jack V setting into the cogs of the wheel W, the swiftest one in the train; this the operator pushes down immediately on the reception of a signal and the weight U sets the whole in motion, drawing the paper off the spool between the rollers x and y, the style impressing on it the required characters, and it rolls finally into the vessel on the left, ready to be read at the convenience of the receiver.

In the earlier forms an alarm was appended to call the attendant's attention, but this is thrown aside, as the click of the register answers the purpose; some experienced operators become so accustomed to this click that they can declare the message without referring to the character made by the style; thus it becomes phonetic, and operators conversing at vast distances, can make the little instrument by its varied action, slow, rapid, or impetuous, give expression to the different feelings of the mind; each office has its own peculiar signal, known to all the rest on the line, and an answer is expected as soon as it is given.

The machine is wound up by a key fixed to the axis of the largest wheel on the left; some guides are used to conduct the paper beneath the style with such regularity that several communications may be printed parallel to each other on the same strip.

The peculiar form of magnet used in the registering department, is seen in the diagram No. 2, to the right of the register. A, A, the circuit connexions; CC, lower extremities of the soft iron bars, which are joined together; HH, reels of the helices around the iron; F F, the upper ends of the soft iron, having opposite polarities; P, the point of connexion between the wires of the two helices; E, the armature; B, above represents the operating key of a distant office, situated on the main line, with the attendant in the act of transmitting a communication; O, the main line coming from the distance; A, the battery on that line; Groves' battery is mostly in use, 30 cups of which are necessary in a space of 150 miles; they may be kept in one body, but it is better to distribute them at intervals along the line; they require cleansing and replenishing about once a fortnight. After passing through the key, the main circuit follows the course of the arrow to the receiving magnet C on the right, traverses the helix of that, and issues again from it, continuing its course to the right, to the next station, and so it might go on indefinitely, or around the world; N, is the local operating key through which the line passes in the same manner as at B; this is the entire relation of the main circuit to an office; it makes the receiving magnet close the local circuit, and it will do it not only at one station, but at all on the same line, and at the same time; so that an operator in Philadelphia, can transmit his message to St. Louis, and drop it at all the intermediate stations at one and the same moment; this has actually been performed.

Only one wire is now used on the main line, the earth affording the return circuit; No. 3, shows it very well; one end of the line may be supposed at Philadelphia, the other at New York; M M, receiving magnets of the two stations; K K, the operating keys respectively, P and N, the positive and negative poles of a battery on the line: C C, plates where the wires terminate in the ground: the connexion of the wires to a gas pipe, will answer every purpose; the arrows represent the direction of the current; G, that portion of the ground forming the circuit. By having two wires, one connected respectively to the keys and magnets of the different offices, communications may be sent both ways at the same time, but only one current can traverse the same line at once.

The local circuit Z is short, simple, and effective, being closed by the receiving magnet; C the current starts from the local battery R, consisting usually of from two to three cups, that must be cleansed every morning for efficient operation, runs through the helix D, back to the receiving magnet in the course of the arrow to the local battery; this causes the style to raise and make an impression on the paper; the whole operation then is very simple; the key depressed at a distant city or station, B causes the receiving magnet C, at Philadelphia, to close the local circuit: the iron of the helix is made instantly magnetic, and the style goes against the paper, and stays there as long as the key is kept down at B. A simple contact makes a dot (), a longer time a line (-). Considerable experience is requisite to make a good operator, either to transmit or read messages; some, however, become quite proficient after three months tuition; the interval between the times of contact, is regarded as well as the letter, for by its length, letters, words and sentences, are distin

guished from each other; the adjoined table contains the Morse Telegraphic characters.

If an operator at Philadelphia, wishes to send a communication to Baltimore, he first breaks the main circuit by opening the operating key at his station. All the receiving magnets in that circuit cease to attract their armatures, the spring draws them away from the magnets, and thus breaks all the short office circuits. The Philadelphia operator then makes the signal for Baltimore, by tapping on his key, the proper number of times; this produces a clicking of the registers, which is heard and understood in all the offices on the line, though none but the Baltimore operator pays any regard to it.

Then the Baltimore operator opens his transmitting or operating key, and breaks the main circuit in another place, so that the Philadelphia operator cannot operate his main circuit, which the latter discovers by the silence of his own receiving magnet when he operates his key; he then closes his key to permit the operator at Baltimore to return an

answer.

The Baltimore operator closes his key, sets his clock work in motion, and returns word that his Philadelphia correspondent may send his communication which the latter hears, and goes to work accordingly.

If the Philadelphia operator wishes to telegraph his message to several or all the stations on the line, he makes in succession, all the signals of those offices, and awaits their replies; after receiving them all, he commences to operate, and the cominunication is received by every one of them at the same moment.

The daily performance of this machine is to transmit from 8000 to 9000 letters per hour; there are a number of attendants needed about an office transacting much business, each one of whom has his respective department: they are divided into "copyists, book keepers, battery keepers, messengers, line inspectors and repairers"; the usual charge of transmission is 25 cts. for ten words sent one hundred miles; the messages vary in value from 10 cts. to $100; the amount of business which a well conducted office can perform, and the nett proceeds arising therefrom, may well excite our surprise; a single office in this country with two wires, one 500, the other 200 miles in length, after spending three hours in the transmission of public news, telegraphed in a single day, 450 private messages averaging 25 words each, besides the address, sixty of which were sent in rotation, without a word of repetition.

The public journals, however, often contain notices of errors committed by the operators on these lines, which, from their importance, have been the cause of considerable complaint among business and newsmen. This is variously attributed to careless attendants, disarrangement of the

circuits, or the alphabetic combination, which renders the best receivers and copyists liable to mistake; this is not all, for instances can be cited where messages sent immediately, as the clerks promised to do, would have answered the desired end, but being delayed three hours, were utterly valueless.

Several important things are necessary to the successful operation of the instrument; skilful manipulators, good batteries and machines, and more than all, thorough insulation of the conductors; the latter can never be completely accomplished, as the best non-conductors will conduct in a slight degree. Copper wire first employed, has, on account of expense, been laid aside for iron, of which 300 lbs. are required to a mile: the method of insulation consists in winding them around glass knobs, passing them through caps of the same material, or enclosing them throughout with gutta percha.

"The figure shows the methods Fig. 28.

3

of attaching them to glass caps, by
supporting the wire from their side
(1,) or resting them in a groove on
the top (2,) these caps fit over
wooden or iron pins, which are
fastened on the top of horizontal
cross bars, or driven into the side of
the post; two blocks of glass in the
form of a parallelopiped, and dove-
tailed together in such a manner,
as to let a wire, without any other
fastening, slide through a central
opening; the glass being surround-
ed and protected by wood; the
most recent method consists of glass
blocks, fitted in cast iron caps and
supported on the peg by a heavy
glass tube (3.) The caps, of

whatever form, are either upon cross bars, or supported by iron staples driven into the post."

Notwithstanding these precautions, by the contact of wires blown about by winds, moisture, &c., connexions are made through the ground. or otherwise, and a short circuit is formed, instead of going the entire route of the line, or part of the current of greatly diminished intensity, pursues the latter course.

The following method of ascertaining the existence of a break, or forming connexions with different offices at will, is well described by Mr. Chas. T. Chester of New York, in Silliman's Journal, Vol. v. 2d, series. It has been found that the intermediate offices on a main line are of great utility in determining the situation of the breech.

If the circuit is broken on one side, a current is at once obtained from the battery of the unbroken side, and the accident found is repaired. The diagram shows how to apply this test, and the method of dividing the long line into sections. The black dots, A B C D, in Fig. 31, represent brass terminations of conductors, sunk on a level with the surface of the