From a short story by P.G. Wodehouse:
Well, you know how it is when you're in some public spot and a stranger comes in wearing the old school tie. You shove a hasty hand over your own and start to sidle out before the chap can spot it and grab you and start gassing. And Barmy was doing just this when the barmaid uttered these sensational words:
"Good evening, Mr. Briscoe."
Barmy stood spellbound. He turned to the barmaid and spoke in a hushed whisper.
"Did you say "˜Briscoe'?"
"From the Vicarage?"
Barmy quivered like a jelly. The thought that he had had the amazing luck to find in the brother of the girl he loved an old schoolmate made him feel boneless. After all, he felt, as he took his hand away from his tie, there is no bond like that of the old school. If you meet one of the dear old school in a public spot, he meant to say, why, you go straight up to him and start fraternizing.
He made a beeline for the chap's table.
"I say," he said. "I see you're wearing a ..."
The chap's hand shot up to his tie with a sort of nervous gesture, but he evidently realized that the time had gone by for protective measures. He smiled a bit wryly.