Sydney also was included in the invitation, and the two lads followed Captain Garcia to the little compartment in which the delicate instruments were installed. The operator, a bright-faced foreigner, stood up civilly as the three entered, and took the message held out to him by Captain Garcia. “Send this to the American battle-ship,” he ordered. “We shall remain here to see you manipulate your instruments.” The wireless man smiled proudly as he put his hand carelessly on his sending key. “What is her call letter?” he asked politely, turning to Phil. “A-D,” the lad replied promptly. The switch was closed and the whirring of the mercurial motor showed the expert that all was ready to commence. The man closed his key and on releasing it a bright spark jumped across the spark gap, charging the storage jars with electrical fluid of a high tension. The lads understood that this had electrified the aerial wire leading to the main truck of the cruiser and a wave of electricity had been started on its journey through space. Again and again in long and short makes and breaks the key was pressed down upon its platinum contact. A-D in dots and dashes was sent up to the long wire. After a minute the key was held at rest and another switch was thrown in, connecting this same wire to the receiving instruments. All held their breath in expectancy while the operator placed his telephone receiver to his ear. Phil watched the man’s face anxiously. He saw on it a look of satisfaction. Then he saw him again close his key, press it down twice in acknowledgment, then glance at the paper before him. A hundred miles away the aerial wire of the “Connecticut” was set in electrical vibration. The American operator below the armored deck heard an even but indistinct buzz in his telephone receiver. He listened intently. It was surely his own call. Who could be signaling him. He must be sure, for he did not wish to interfere with the messages among the foreign war-ships. No, it was distinct enough. A-D, A-D, unceasingly. He waited until the noise ceased, then quickly he sent out his acknowledgment, turning the rheostat handle for high tension, for he knew the sender of this mysterious call was at a long distance. “I have her, señor captain,” the operator of the “Aquadores” reported in a businesslike voice as he proceeded to send the cipher message before him. Phil breathed easier after the last acknowledgment had been received from the “Connecticut.” The captain in but a few minutes would know the situation as well as if they themselves had told him in person. “Now that this is off our minds,” exclaimed Phil, as he and Sydney walked up and down outside the captain’s cabin, “I believe it our duty to discover how strong this ship is for fighting two of her enemy’s vessels. I am delighted to be here, but at the same time I don’t care about getting killed, or what might be worse, captured. If our friend Ruiz gets us in his power again, it will be all up with us.”