“It was this way,” explained Roy. “When I got into touch with her wireless man, he asked if we could hear the Merrimack’s whistle. He said they could distinctly hear ours. At least he supposed it was ours. I listened and heard the whistle, but one time it seemed near and again far off. I couldn’t tell from what direction the sound came.”
“Correct,” said Mr. Young. “We heard it, too. Fog does the strangest things to sound. That’s what makes it so dangerous for ships. The officer in charge can usually hear another ship, but sometimes he can’t for the life of him tell what direction the sound comes from.”
“Well,” continued Roy, “it occurred to me that if the Merrimack’s whistle and her wireless instrument could signal at the same instant I could tell how far away she was.”
“How?” asked the first mate, more interested than ever.
“Why, you know, Mr. Young, electricity is instantaneous, while it takes sound a second to travel a thousand feet. If the two signals started together, I could time the difference between their arrivals. It was simple enough if only the Merrimack could send the signals right.”
“Now what do you think of that?” cried the mate. “How did you manage it?”
“The Merrimack’s wireless man did that. I asked him if he could. He said he would talk to the captain and they would set their watches together and each signal at the same instant. All I had to do was listen to the signals and catch the time between them.”
“Well, I’ll be darned!” ejaculated the first mate. “I never heard anything like it. Is that what they teach you at the radio school?”
“I’ve never been to one,” said Roy. “All I know about wireless I picked up myself.”
The first officer regarded Roy with astonishment. “Well, you’re a pippin,” he said.