“Oh, dry up, for Heaven’s sake! You’re not funny, Roger.”

“That,” Roger maintained firmly, “is a matter of opinion. Well, let us talk very seriously about gulls. There are no less than seven hundred and forty distinct species of gulls known to the entomologist, of which one hundred and eighty-two may be found by the intrepid explorer around the rocky coasts of these Islands. Perhaps the most common variety is the Patum Perperium, or Black-hearted Wombat, which may be distinguished by⸺”

“What are you talking about?” demanded his bewildered listener.

“Gulls, Anthony,” replied Roger, and went on doing so with singular ardour right up to the ledge itself.

“Hullo, Margaret,” he greeted its occupant pleasantly. “Anthony and I have been talking about gulls. Do you think you could invite us to tea this afternoon with you?”

“To tea? Whatever for?”

“Well, it’s such a long way back to our own. Yours is so much easier.”

“Don’t take any notice of him, Margaret,” Anthony advised. “He’s only being funny. He’s been funny ever since we left the Crown.”

“Yes, and about gulls, too,” Roger added with pride. “Extraordinarily difficult things to be funny about, as you’ll readily understand. But I’m quite serious about tea, Margaret. I want to have a chance of studying the occupants of your household at close quarters.”

“Oh, I see. But why?”