Curiosities of Civilization

by Andrew Wynter

These switches, testing, and battery boxes are of great service in certain conditions of the atmosphere. For instance, a thunderstorm, or more often a fog, will now and then so affect the conducting power of a wire, working through a long distance, that it is found impossible to send a message along it, in which case the clerk “dodges” the passing storm or fog by switching the dispatch round the country through a fine-weather wire. If however the foggy weather should continue, the manipulator has only to go to the battery box and couple on one or more batteries, just as fresh engines are put on a train going up an incline when the rails are “greasy.” By thus increasing the power of the electric current the message is driven through the worst weather. Sometimes as many as six or eight 24-plate batteries are necessary to speed a signal to Glasgow. The more general way in such cases, however, is to transmit the dispatch to some intermediate station, where the message is repeated.

Let us now descend into the battery vaults—two long narrow chambers, situated in the basement of the building. Who would think that in this quiet place, night and day, a power was being generated that exerted its influence to the very margin of this seagirt isle, nay, invaded the territories of Holland, Belgium, and France? Who would think that those long dusty boxes on the shelves were making scores of iron tongues wag hundreds of miles off? There are upwards of sixty Daniel’s batteries in full employment in these vaults. They are ranked as sixes, twelves, and twenty-fours, according to the number of their elements or plates; and just like guns, the higher they rank the further they carry. The powerful twenty-fours work the long ranges of wire, and the smaller batteries the shorter circuits. Of course some of these batteries have harder work to do than others, and the “twenty-fours” working the North-Western line have much the busiest time of it. Considering the work done by them, their maintenance is not very costly. A twenty-four, when in full work, does not consume its zinc plates under three months, and a gill of sulphuric acid, diluted, is its strong but rather moderate allowance of liquid per month. Other batteries of the same force are satisfied with 1 lb. of sulphate of copper per month, with a little sulphate of zinc, and salt and water. The entire amount of electric power employed by the Company throughout the country is produced by 8000 12-plate batteries, or 96,000 cells, which are lined with 1,500,000 square inches of copper, and about the same of zinc. To work these batteries six tons of acid is yearly consumed, and fifty-five tons of sand; the principal use of the latter is to prevent the chemicals from slopping about, and the metal plates from getting oxidised too rapidly. The language of the “wire,” with respect to the working of the telegraph, is very curious. For instance, when a distant station-clerk finds that a battery is not up to its work, by the weak action of the needles, he sends word that it requires “refreshment,” and it is accordingly served with its gill of aquafortis, and, totally opposed to the doctrines of temperance, a “long-lived battery” owes its vitality to the strongest drink.

We have followed the wires down to one pole of their respective batteries, and now we have to pursue them out of the opposite pole until they take to “earth.” No electricity will flow from the positive pole Z of the battery (Fig. 2) unless the wire D K A B is connected, either by being itself unbroken, or by the interposition of some other conductor where a gap occurs, to the negative pole C. In the earlier telegraphs it was usual to have a return-wire to effect this purpose. But, strange as it may sound, it was discovered that the earth itself would convey the current back to the negative pole, and thus an entire length of wire was saved. Accordingly the earth completes the two hundred and odd different circuits, which pass their loops, as it were, through the central office. In order to get a “good earth” a hole was dug deep in the foundations, until some moist ground was found, dry soil being a very bad conductor, and into this a cylinder of copper, four inches in diameter and 40 lbs. in weight, was sunken, surrounded by a mass of sulphate of copper in crystals. All the earth wires of the establishment were then put in connection with this mass of metal, or earth plate.

The non-scientific reader will perhaps require a figure to explain to him our meaning, when we say that the earth is capable of completing the “circuit.” In the accompanying diagram (No. 6) we have a battery, U V, in the central office in London, deflecting a needle N, say in Liverpool. The fluid passes from the positive pole of the battery U, traverses the wire of the North-Western Railway, and after working the telegraph in Liverpool, descends into the earth by the wire B, which has a metal or earth-plate attached to it. From this point the electric fluid starts homewards, through the solid ground, and finding out the earth-plate[38] under the foundations at Lothbury, ascends along the wire A, into the negative pole of the battery V. By reversing the current, it flows first through the earth from V A to B, and returns by the wire to the opposite pole U.

Nothing in telegraphy impresses the thoughtful mind more than the fact that the electric fluid, after spanning, maybe, half the globe, should come back to its battery, through adamantine rocks, through seas and all the diverse elements which make up the anatomy of the globe. The explanation of the phenomenon is still a matter of pure speculation. Indeed, it may be objected that our flight of the electric principle is altogether a flight of fancy—that there is in fact no flow of electricity at all, but that its progress through bodies, according to the generally received theory, is owing to opposite poles of contiguous particles acting upon each other. The hypothesis, however, first received in science gives birth to its language, which usually continues the same, although it may have ceased to be an adequate expression of the current doctrine of philosophers.

The traveller, as he flies along in the train, and looks out upon the wires which seem stretched against the sky like the ledger lines of music, little dreams of these invisible conductors that are returning the current through the ground. In ninety-nine cases out of a hundred, indeed, the wires and their sustaining posts represent to the spectator the entire telegraph. The following conversation between two navigators, overheard the other day by a friend, gives the most popular view of the way the telegraph works. “I say, Jem, how do ’em jaw along them wires?” “Why, Bill, they pulls at one end, and rings a bell at t’other.” Others again fancy that messages are conveyed by means of the vibrations of the metal, for on windy days they sometimes give out sounds like an Æolian harp: a fact which, according to Sir Francis Head, called forth the remark from a North-Western driver to his stoker, “I say, Bill, aint they a giving it to ’em at Thrapstone?” The more ignorant class of people actually believe that it conveys parcels and letters, and they sometimes carry them for transmission to the office.

Iron wire, coated with zinc, or “galvanised,” as it is termed, to prevent its rusting, is now universally used as the conductor of the electric fluid when the lines are suspended in the air. The first rain falling upon the zinc converts it into an oxide of that metal, which is insoluble in water, so that henceforth in pure air it cannot be acted upon by that element, and all further oxidation ceases. Mr. Highton says, however, that in the neighbourhood of large manufacturing towns the sulphur from the smoky atmosphere converts the oxide into a sulphate of zinc, which is soluble, and consequently the rain continually washes it off the wire. He asserts that he has had wires in this manner reduced from the eighth of an inch to the diameter of a common sewing-needle. There has been a great controversy as to the best means of insulating the wires from their supporting-poles, which would otherwise convey the electricity from the wires to the earth. There is no method known of effecting this completely, but we believe it is now decided that stoneware is the best material for the purpose, both on account of its non-conducting qualities, and the readiness with which it throws off from its surface particles of water. The latter quality is extremely important, for, in very rainy weather, if the insulator should happen to get wet, the electric fluid will sometimes make a bridge of the moisture to quit the wire, run down the post to the earth, and make a short circuit home again to its battery. Indeed, when there are many wires suspended to the same pole on the same plane, a dripping stream of water falling from an upper to a lower one will often suffice to return the current before it has done its work, much to the telegraphist’s annoyance. Not long ago, a mishap, having similar consequences, occurred on the line between Lewes and Newhaven, owing to the following very singular circumstance: a crane, in its flight through the rain, came in contact with the wires, and having threaded his long neck completely through them, the current made a short cut along his damp feathers to the wire below, and by this channel home. Moisture, however, much as it may interfere for a time with the working of a line, rarely does any permanent injury. Lightning, on the contrary if not guarded against, is capable of producing great mischief. It has been known to strike and run for miles along a wire, and, in its course, to enter station after station, and melt the delicate coils and the finer portions of the instruments into solid masses. In most cases it reverses the polarity of the needles, or renders permanent the magnetism of the electro-magnets. All these dangerous and annoying contingencies are easily avoided by the application of a simple conducting-apparatus to lead away the unwelcome visitor. The method adopted by Mr. Highton is to line a small deal box, say ten or twelve inches long, with a tin plate, and to put this plate in connection with the earth. The wire bound up in bibulous paper—which is a sufficient insulator for the low-tensioned fluid of the battery—is carried, before it enters the instrument, through the centre of the box, and is surrounded with iron fillings. The high-tensioned electricity of the lightning instantly darts from the wire, through the pores of the paper, to the million points of the finely-divided iron, and so escapes to the earth. There are, of course, many kinds of lightning conductors used on different lines, but this one is simple in its construction, and, we are given to understand, answers its purpose exceedingly well.

Notwithstanding that the Electric Telegraph Company has been established so many years, it is only just now that the public have begun to understand the use of the “wire.” The very high charges at first demanded for the transmission of a message, doubtless, made it a luxury rather than a necessary of life; and every reduction of the tariff clearly brought it within the range of a very much larger class of the community, as will be seen by the following table issued by the Company, which shows the advance of the system under its management.