that the first thing to do is to find out whether one of our own operators is in on this or not. Unless the line is tapped somewhere, it's a cinch that a station key is being used, isn't it? Send some linemen that you can trust over the division. If they find anything at all, they'll find the spot where the messages are coming from, won't they? If they find nothing, we'll know we've got to look nearer home—amongst our own men."
Lanson, in his turn, shook his head.
"Not necessarily," he objected. "We've a number of small stations where there's no night operator. They might have got into one of those. The messages all come through at night."
"Well, I'll call the turn there!" responded MacVightie, with a short laugh. "See that I get a list of those stations in the morning, and I'll detail men to take care of that end of it."
The Hawk drew back a little, shifting his strained position—the amused smile was no longer on his lips.
"And as for that 'ground' business," went on MacVightie, "go slow with it till you get your linemen's report. Don't do any more than try it out with some operator you can absolutely depend upon, say, about halfway down the line. You say you would be able to tell whether the messages were coming from east or west of that point; that'll cut the division in half for us as far as our search is concerned, and that's worth taking a chance on. But don't overdo it, Lanson. We don't want to throw any scare into him—yet."
