"But what did he do?" demanded Mollie impatiently. "You haven't gotten to the point yet."

"Well," Allen continued, while Betty put a sympathetic arm about her friend and snuggled close, "all the time we were wondering down in our hearts why Will didn't enlist—although we never doubted he had good reasons," he added hastily, "he was really working harder, spending more time and energy for the government than we ever thought of spending. There's one important thing we forgot—that Will was a secret service man!"

"Oh!" cried Betty, her eyes gleaming in the firelight, "now, I know I guessed right!"

"What did you guess?" asked Allen, remembering to marvel, even in that moment of excitement, how very becoming firelight was to Betty! "Out with it."

"Why," said Betty, leaning forward eagerly, "after Amy told us that she had met Will and the soldiers half way to the spot where we found the spy, I seemed to see the whole thing as plainly as if some one had told it to me.

"I remembered Will's special interest in the spy the first time we met Adolph Hensler on Pine Island—then how, soon after we saw him here again, Will wrote Grace that he was coming on. That would seem as though he were hot on his trail—"

"He was," said Allen, while the others hung on every word.

"Well, the rest is simple," said Betty. "I suppose that Will kept on shadowing him till he got what he wanted. He was on his way to capture the spy, while we were hanging on to the door, praying for help. Oh, it all fits together like parts of a puzzle!"

"You're a wonder, Betty!" said Allen, while the others drew a deep breath, trying to take it all in. "But there was one little bit, or rather, I should say, big bit, of cleverness on Will's part that neither you nor anybody else could guess at. You remember the code letter we picked up that night on Pine Island?"

"Yes," they cried eagerly.