CHAPTER XVII.
IN THE LABORATORY.
That afternoon Jack broached to his father the events of the morning. Mr. Chadwick's enthusiasm may be imagined as his son told him of the professor's hasty analysis of the contents of Zeb Cumming's glass vial.
But there remained the insuperable obstacle of the remoteness of the island where the deposits lay, and the difficulties—in fact, almost the impossibilities—that barred the way. For the time being, however, the matter was set aside while further experiments with the radio telephone were conducted. As a means of increased transmitting power, Mr. Chadwick had in mind a series of sending devices attached to one mouthpiece. In this way he believed he could at least partially overcome the resistance of the atmosphere, and get a higher percentage of current.
He had been working on the idea all the morning and was anxious for a test. The Wondership was, therefore, wheeled out, and before long the boys were in the air once more. As before, they sailed in the direction of Rayburn. As they passed above the farm where they had met with their adventure the day before, they turned to each other with a laugh.
Below them they could see men working on the damaged roof of the barn and Tom burst into an uncontrollable fit of laughter as he recalled the queer sight the farmer presented dangling from the grapnel high above his broad acres.
"That reminds me," said Jack. "We must send him some money for that roof."
"How about his personal feelings?" grinned Tom.
"I guess he wiped that score out when he blazed away at the balloon bag."
"Just the same, I think we'd better go pretty high up," advised Tom. "He might fancy trying another shot at us."
"That's so," agreed Jack, studying the men moving about far below.
He pulled a lever and the Wondership began to rise. It was as well he did so perhaps, for as they shot upward they could see that their presence had been noted. They watched the men scurrying about and pointing upward. But whether the Wondership was too high, or his animosity had cooled after his involuntary ascension, the farmer made no hostile demonstration, and they were soon out of Perkins' sight.
Apparently the new device worked fine, for all through the afternoon, at various heights and distances, they kept in perfect touch with Mr. Chadwick. Every intonation of his voice was borne plainly to their ears, Tom at times taking the wheel and the receivers while Jack relieved him at the engines.
The storm which had threatened the night before, still was hovering about, as was evidenced by the white thunderheads piled on the horizon. But the electricity in the air did not, as is sometimes the case, interfere with the powerful impulses sent out from workshop and airship. Although the air felt heavy, the instruments worked perfectly.
The boys flew over hill and dale for more than seventy miles prior to any perceptible weakening in the current. But once it began to fail it reduced rapidly until the messages were scarcely audible. But the experiments were kept up till almost dusk, when Mr. Chadwick told the boys to come back.
As they returned the radio 'phones were kept working and as the distance decreased the impulses grew stronger.
"If only I had some of that Z.2.X.," said Mr. Chadwick, "I believe it would be possible to send a message across the ocean or the continent."
Not long after this Jack heard again from his father. It was a commonplace message enough. Sent merely to keep the air-line in operation.
"Here is Jupe with the afternoon mail," he said.
"Anything for us?" asked Jack, enjoying the novel sensation of talking through the air concerning such everyday matters.
"Yes, there's one from Ned Nevins," was the rejoinder, "and here is one for me from my New York brokers. Let me see—ah-h-h-h!"
The last was a sharp exclamation, as if Mr. Chadwick had received a sudden shock. It was followed by silence. Again and again Jack flashed the red signaling lamp but there was no reply.
He was seriously worried. The sudden sharp intake of breath, almost like an outcry, that he had heard, oppressed him with a sense of apprehension. What could have happened? Turning to Tom he called for full speed ahead for the trip back.
Tom was not slow in responding. He speeded the motors up to their top capacity. In the air there were no speed laws to look out for, or other motorists or pedestrians to avoid. It was a clear road. The steel stays and stanchions of the stanch Wonder ship fairly hummed as she shot forward, while an indefinable fear clutched at Jack's heart.
He knew that his father was subject to fainting spells and he had been overworking recently. Fast as the Wondership was cutting through the air it felt like an eternity to Jack before the gray walls and the well-laid-out grounds of High Towers came into view.
The boys lost no time in landing, and not waiting to place the Wondership in her shed, set out to look for Mr. Chadwick. Jupe came shuffling by on his way from the cornpatch.
"Where's dad, Jupe?" asked Jack.
"In his labveroratory, ah reckons," answered the old colored man. "Leastways ah ain't obfustucated any obserwations ob him round der contagiois atmosferics."
"Come on, Tom," said Jack. "Let's get to dad's workshop as quick as we can."
"Why, Jack, you—you don't think that anything has happened to him, do you?" asked Tom.
"I don't know. He was talking quite cheerfully to me and then, without any warning, he gave a sort of gasp and then everything was silent."
The next minute the boys entered the workshop of the inventor.
Jack's worst fears were realized as they gazed at the scene before them. On the floor, stretched out inanimate before the radio telephone apparatus, lay Mr. Chadwick. His right hand grasped a letter.
His head lay in a pool of blood, oozing from a cut at the back of his head.
"Dad! dad! What has happened?" cried Jack, in an agony of alarm, as he fell to his knees at his father's side.
But Mr. Chadwick did not answer. The next moment Tom's shout for help brought everybody about the place running toward the workshop where the alarming discovery had been made.