She was deep in the mystery of it when a voice startled her. It came from back of the cabinet.
"I say," the voice sang cheerily, "have you any letters in your little
P. O. on the hill?"
The voice thrilled her. It was new and sounded young.
"Yes," she said, throwing open the back of the cabinet and standing up, "we have, quite—quite a variety."
The visitor was young, not more than twenty, she thought.
"What color?" she said teasingly, as she stepped from her cabinet.
"Blue," he said seriously.
"Blue?" She started. The mysterious letter was blue; the only blue one she had seen for months.
"What name?"
"Well, you see," the young man flushed, "not—not any real name; just the Greek letters, Phi Beta Ki."