And now see how an initial hypothesis may pursue and overtake its maker. Our thumb-marks have been taken, they have travelled by pneumatic tube to the central office of the municipality hard by Lucerne, and have gone on thence to the headquarters of the index at Paris. There, after a rough preliminary classification, I imagine them photographed on glass, and flung by means of a lantern in colossal images upon a screen, all finely squared, and the careful experts marking and measuring their several convolutions. And then off goes a brisk clerk to the long galleries of the index building.

I have told them they will find no sign of us, but you see him going from gallery to gallery, from bay to bay, from drawer to drawer, and from card to card. “Here he is!” he mutters to himself, and he whips out a card and reads. “But that is impossible!” he says. . . .

You figure us returning after a day or so of such Utopian experiences as I must presently describe, to the central office in Lucerne, even as we have been told to do.

I make my way to the desk of the man who has dealt with us before. “Well?” I say, cheerfully, “have you heard?”

His expression dashes me a little. “We’ve heard,” he says, and adds, “it’s very peculiar.”

“I told you you wouldn’t find out about us,” I say, triumphantly.

“But we have,” he says; “but that makes your freak none the less remarkable.”

“You’ve heard! You know who we are! Well — tell us! We had an idea, but we’re beginning to doubt.”

“You,” says the official, addressing the botanist, “are ——!”

And he breathes his name. Then he turns to me and gives me mine.

For a moment I am dumbfounded. Then I think of the entries we made at the inn in the Urserenthal, and then in a flash I have the truth. I rap the desk smartly with my finger-tips and shake my index-finger in my friend’s face.

“By Jove!” I say in English. “They’ve got our doubles!”

The botanist snaps his fingers. “Of course! I didn’t think of that.”

“Do you mind,” I say to this official, “telling us some more about ourselves?”

“I can’t think why you keep it up,” he remarks, and then almost wearily tells me the facts about my Utopian sel............