"He's clever all right," Darrow murmured admiringly to Jack. "See what he's up to?"
"Not yet," muttered Jack.
The substitution completed, Eldridge again glanced at his watch.
"Now," he instructed Simmons, "send the letters 'Q E D,' and continue to do so until you again hear the letters 'O K Q.'"
Simmons set himself to the task. It was a long one. At last he reported his answer.
"He sends 'O K Q ten,'" he said.
Eldridge turned to the reporters.
"That means that the substitution of the smaller Leyden jar for one of the larger reduced the sending power of this instrument just ten miles," said he. "My crew has quite simply moved slowly forward until it caught our sending here."
"Next," he instructed Simmons, "see if you can communicate with Monsieur
X."
The operator speedily reported his success at that. Eldridge removed his glasses and polished their lenses.