"There's lots of things just as hard to understand, only you take them for granted. Being alive, for instance. Look at Mollie fidgeting about, and Long John chewing and twitching, and the trees waving their branches, and you shaking your head as if it were a dinner-bell, which is about what it is—it's all life. Just as hard to understand as Relativity, and a jolly sight harder if you ask me. I can't say I understand Time-travelling, but—" Jerry broke off.

Mollie frowned thoughtfully. "We don't understand it yet," she said, "but in another forty years—"

They were all silent. Another forty years!

"We'll be fifty-three," Dick said at last. "A jolly funny looking lot we'll be. All sitting round staring at each other through specs, with white hair and no teeth worth mentioning. I'll have an ear-trumpet, and Mollie will wear a cap like Grannie's, and Jerry will be a blithering old idiot saying, 'Hey!' like General Dyson-Polks."

They had to laugh at this picture of themselves, and then Mollie began at the beginning and told the story of Prue's first visit. The boys were deeply interested. Their own experiences had merely been a repetition of the first—Hugh had appeared and, like the gentleman who dealt in Relativity, they were Here and they were There. "It has taught us something about Australia anyhow," said Dick; "that is, of course, if we saw the real thing. The next thing is to find out whether we did or if the whole show was just bunkum."

"What I should like to know," said Jerry reflectively, "is who the Campbells were, and how they got mixed up with your lot. They must have at some time, or your people wouldn't have those photographs."

Mollie smiled. She knew how they and the Campbells had got "mixed up", but she had never told the boys of her discovery; it was a little secret between her and a certain photograph that smiled down at her from the morning-room mantelpiece. She liked to think how the original would have laughed along with her.

"What I should like to know," said Dick, "is what that chap O'Rourke was doing in that field. What was his mysterious experiment, and how did Hugh's stone cut into it? That's what I want to know, and I don't suppose I ever will, now. I don't think we'll go back, not at present anyway. The show's over for this time. In fact I don't want to go; I'm too jolly well pleased to be where I am. Gee-up, you lazy brute,"—this to Long John, who apparently thought he had done enough work for one day and was nosing about the soft grass with contemptuous disregard for his passengers. He moved on unwillingly, and Dick took him briskly downhill.

In the village there were old friends to be greeted, and many inquiries for Mollie's ankle to be answered. Fresh crusty loaves were brought out by the baker, loosely wrapped in soft paper, and packed away under the seats. A large box, containing a peculiarly delicious make of sponge cake, was set on Mollie's lap, and a blue paper bag of sifted sugar was entrusted to Jerry's special care by a misguided grocer. Dick had a golf-club needing attention, which entailed a long and intimate conversation with the local carpenter, who was also a well-known local golfer, and the best hand at repairing clubs, Dick was convinced, in the whole of Great Britain.

It was getting on towards tea-time when Long John's head was at last turned homewards, and his feet covered the ground with cheerful and approving swiftness. A drizzle of rain fell, "Just enough to save us the trouble of washing for tea," Dick commented. "Do you think our white aunt can be induced to come and play golf after tea, Moll, or is she afraid of rain?"