“What are those colored pins stuck all over it supposed to be—ships?”
“Yes. Ships within a radius of several hundred miles that have been sending out radio messages.”
“But how does he do it?”
“Oh, I guess our little operator is clever all right. I’m no wireless expert and there are a lot of gadgets in here that I don’t understand. Undoubtedly they’re delicate instruments by which the operator is able to determine the approximate distance and direction of any ship sending out messages. You see, he keeps this map constantly before him, charted with the probable positions of ships. He changes the pins when his new readings seem to be in error. This is how the noble Baron knows exactly what is going on in his neighborhood. Just as if he were looking down on the sea from the moon with a telescope!”
“That list up there beside the chart is the key to the colored pins, I suppose.”
“Sure. There’s the Stamford.” Bill pointed to a gray pin. “Well, here’s where I get busy. The sooner that cruiser is put wise to our position, the better.”
“But how did you find out where we are?” Osceola looked his surprise. “When have you had a chance to shoot the sun? Do you keep a pocket sextant up your sleeve? Or are you just guessing?”
“Nothing like that. A sight must be taken when the sun reaches it’s highest point. I got the dope tonight from Schneider. While you were asleep, I went on the bridge and got him to give me our position this noon.”
“But that’s more than twelve hours ago!”
“Certainly. But I also found out the speed and direction we’ve been steaming this afternoon and evening. Where we are now is a simple sum in arithmetic.”