Page:Popular Science Monthly Volume 5.djvu/319

Rh reduction of the vast fortress as the circle of steel and iron, of batteries, earthworks, and redoubts, which, without the connecting link of the telegraph-wire, could not have been maintained for a single month. On their side the French displayed no less energy. The regular telegraph corps was shut up in Metz or lost at Sedan; but a fresh corps was organized for the armies of the republic, and at Paris the telegraph-lines linked together the enceinte, the forts and outworks, and the headquarters of General Trochu. But it was in the second siege of the capital that the French telegraph corps obtained its greatest success. During the fighting in the streets of Paris, in May, 1871, the moment a barricade was taken, a telegraph-station was established in a neighboring house, and when another post was carried the telegraph corps would again move forward with the troops, and thus MacMahon was able to watch every turn of the fight, and provide for every contingency, in a way that otherwise would have been utterly impossible. For ourselves, we have had no European war since 1854; but our armies have carried the telegraph with them into India and China, and through the ravines and passes of Abyssinia; and now the "talking wire" stretches from Cape Coast Castle through the bush, across the Prah into the heart of Western Africa, hanging on the trees, with here and there a few poles, the whole having been erected by Fantee laborers, under the direction of a handful of Royal Engineers.

The object of the field telegraph is to keep the headquarters of an army in communication with its several corps, and, at the same time, with the general telegraph system of the country. In the Prussian army, when the telegraph corps was reorganized after the war of 1866, it was formed into two divisions—the Field Telegraph Division and the Etappen Division—with view to the more efficient performance of these two services. Both divisions consist of several companies or sections, each of which contains about 150 men, including officers, telegraph operators, pioneers, workmen for the erection of the line, and drivers for the station-, store-, and baggage-wagons. In all armies the telegraph matériel is, of course, very similar, and we shall therefore describe that of the Prussian army, adding a few notes on that of other countries.

The two essential portions of the field telegraph are the station and the line. In order that there may always be a sheltered place for erecting the instruments and transmitting messages, each detachment of the telegraph corps carries with it one or more wagons fitted up as stations; but, wherever a halt of more than a few minutes is made, and there is a suitable building available for that purpose, a telegraph-station is established in it by removing the batteries and instruments from the wagon. Fig. 1 is an outline sketch of a Prussian station-wagon, Fig. 2 being a section of the same. The wagon is about 9 ft. long, with an interior height of 4 ft. 6 in., and a width of 4 ft. It is