“I have just returned home after a voyage to South America in one of the Pacific Steam Navigation Company’s cargo boats. When we left Montevideo we heard that France and Germany were at war, and that there was every possibility of Great Britain sending an ultimatum to Germany. We saw several steamers after leaving the port, but could get no information, as few of them were fitted with wireless and passed at some distance off. When about 200 miles east of Rio, our wireless operator overheard some conversation between the German cruiser Karlsruhe and a German merchant ship at anchor in Rio. It was clearly evident that the German merchant ship had no special code, as the conversation was carried on in plain German language, and our operator, who, by the way, was master of several languages, was able to interpret these messages without the slightest difficulty. It was then that we learned that Great Britain was at war. The German cruiser was inquiring from the German merchant ship what British vessels were leaving Rio, and asking for any information which might be of use. We also picked up some news of German victories in Belgium, which were given out by the German merchant ship. It was clearly evident that the Karlsruhe had information about our ship, and expected us to be in the position she anticipated, for she sent out a signal to us in English, asking us for our latitude and longitude. This our operator, under the instructions of the captain, declined to give. The German operator evidently got furious, as he called us an English ‘swine-hound,’ and said, ‘This is a German warship, Karlsruhe; we will you find.’ Undoubtedly he thought he was going to strike terror to our hearts, but he made a mistake.
“That night we steamed along without lights, and we knew from the sound of the wireless signals that were being flashed out from the German ship that we were getting nearer and nearer to her. Fortunately for us, about midnight a thick misty rain set in and we passed the German steamer, and so escaped. Our operator said that we could not have been more than 8 or 10 miles away when we passed abeam. Undoubtedly our wireless on this occasion saved us from the danger from which we escaped.”
Apparently little is known of the end of the Karlsruhe, but the Emden met with the fate she richly deserved; and fittingly enough, wireless telegraphy, which had enabled her to carry out her marauding exploits, was the means of bringing her to her doom. On 9th November 1914 the Emden anchored off the Cocos-Keeling Islands, a group of coral islets in the Indian Ocean, and landed a party of three officers and forty men to cut the cable and destroy the wireless station. Before the Germans could get to the station, a wireless message was sent out stating the presence of the enemy warship, and this call was received by the Australian cruisers Melbourne and Sydney. These vessels, which were then only some 50 miles away, were engaged, along with a Japanese cruiser, in escorting transports. The Sydney at once went off at full speed, caught the Emden, and sent her to the bottom after a short but sharp engagement. As the Emden fled at sight of the Australian warship, the landing party had not time to get aboard, and consequently were left behind. They seized an old schooner, provisioned her, and set sail, but what became of them is not known.
In land warfare field telegraphs play a very important part; indeed it is certain that without them the vast military operations of the present war could not be carried on. The General Headquarters of our army in France is in telegraphic communication not only with neighbouring French towns, but also with Paris and London. From Headquarters also run wires to every point of the firing-line, so that the Headquarters Staff, and through them the War Office in London, know exactly what is taking place along the whole front. The following extract from a letter from an officer, published by The Times, gives a remarkably good idea of the work of the signal companies of the Royal Engineers.
“As the tide of battle turns this way and the other, and headquarters are constantly moving, some means have to be provided to keep in constant touch with General Headquarters during the movement. This emergency is met by cable detachments. Each detachment consists of two cable waggons, which usually work in conjunction with one another, one section laying the line whilst the other remains behind to reel up when the line is finished with. A division is ordered to move quickly to a more tactical position. The end of the cable is connected with the permanent line, which communicates to Army Headquarters, and the cable detachment moves off at the trot; across country, along roads, through villages, and past columns of troops, the white and blue badge of the signal service clears the way. Behind the waggon rides a horseman, who deftly lays the cable in the ditches and hedges out of danger from heavy transport and the feet of tramping infantry, with the aid of a crookstick. Other horsemen are in the rear tying back and making the line safe. On the box of the waggon sits a telegraphist, who is constantly in touch with headquarters as the cable runs swiftly out. An orderly dashes up with an important message; the waggon is stopped, the message dispatched, and on they go again.”
Wireless telegraphy too has its part to play in land war, and for field purposes it has certain advantages over telegraphy with wires. Ordinary telegraphic communication is liable to be interrupted by the cutting of the wire by the enemy, or, in spite of every care in laying, by the breaking of the wire by passing cavalry or artillery. No such trouble can occur with wireless telegraphy, and if it becomes necessary to move a wireless station with great rapidity, as for instance on an unexpected advance of the enemy, it is an advantage to have no wire to bother about. The Marconi portable wireless sets for military purposes are marvels of compactness and lightness, combined with simplicity. They are of two kinds, pack-saddle sets and cart sets. The former weigh about 360 lb., this being divided amongst four horses. They can be set up in ten minutes by five or six men, and require only two men to work them. Their guaranteed range is 40 miles, but they are capable of transmitting twice this distance or even more under favourable conditions. The cart sets can be set up in twenty minutes by seven or eight men, and they have a guaranteed range of from 150 to 200 miles.
It is obviously very important that wireless military messages should not be intercepted and read by the enemy, and the method of avoiding danger of this kind adopted with the Marconi field stations is ingenious and effective. The transmitter and the receiver are arranged to work on three different fixed wave-lengths, the change from one to another being effected quickly by the movement of a three-position switch. By this means the transmitting operator sends three or four words on one wave-length, then changes to another, transmits a few words on this, changes the wave-length again, and so on. Each change is accompanied by the sending of a code letter which informs the receiving operator to which wave-length the transmitter is passing. The receiving operator adjusts his switch accordingly, and so he hears the whole message without interruption, the change from one wave-length to another taking only a small fraction of a second. An enemy operator might manage to adjust his wave-length so as to hear two or three words, but the sudden change of wave-length would throw him out of tune, and by the time he had found the new wave-length this would have changed again. Thus he would hear at most only a few disconnected words at intervals, and he would not be able to make head or tail of the message. To provide against the possibility of the three wave-lengths being measured and prepared for, these fixed lengths themselves can be changed, if necessary, many times a day, so that the enemy operators would never know beforehand which three were to be used.
Wireless telegraphy was systematically employed in land warfare for the first time in the Balkan War, during which it proved most useful both to the Allies and to the Turks. One of the most interesting features of the war was the way in which wireless communication was kept up between the beleaguered city of Adrianople and the Turkish capital. Some time before war broke out the Turkish Government sent a portable Marconi wireless set to Adrianople, and this was set up at a little distance from the city. When war was declared the apparatus was brought inside the city walls and erected upon a small hill. Then came the siege. For 153 days Shukri Pasha kept the Turkish flag flying, but the stubborn defence was broken down in the end through hunger and disease. All through these weary days the little wireless set did its duty unfalteringly, and by its aid regular communication was maintained with the Government station at Ok Meidan, just outside Constantinople, 130 miles away. Altogether about half a million words were transmitted from Adrianople to the Turkish capital.
PLATE XVI.
