"It's a grave accusation to make, but I can hit on no other explanation of his actions. He is angry at us because he thinks we may see too much. Look, they are still signalling."
"I wish we could read what they are saying."
"I think I can," rejoined Rob quietly.
"You can?"
"Yes."
"How are you going to do it?"
"By bringing my knowledge of Morse into play. I think that when the flag is run up slowly it means a dash and a quick run is a dot. Let's try it anyway."
Luckily the spot where the two boys were was grown with high, coarse grass, and the sand dunes rose high in places, affording protection for them.
As the flag rose and fell they spelled out a word according to the Morse code.
"That's 'Ready'," proclaimed Rob exultingly; "we have hit on their code, all right."