our thoughts.

"For a moment there was dead silence--long enough for the professor to
grasp the full significance of what had passed. Then he uttered a
single exclamation, 'Oh!'

"After a while, however, he looked at me for the first time that
evening, saying, 'Congratulate you, Mr. Kensett, I'm sure,' tied
several knots in the cord of his dressing-gown, lighted a cigar, and
paid no further attention to either of us. Some moments later he
opened the window again and disappeared. I looked across the aisle at
Wilhelmina.

"'You may come over beside me,' she said, shyly.

XXV

"It was nearly ten o'clock and our train was rapidly approaching
Paris. We passed village after village wrapped in mist, station after
station hung with twinkling red and blue and yellow lanterns, then
sped on again with the echo of the switch-bells ringing in our ears.

"When at length the train slowed up and stopped, I opened the window
and looked out upon a long, wet platform, shining under the electric
lights.

"A guard came running by, throwing open the doors of each compartment,
and crying, 'Paris next! Tickets, if you please.'

"I handed him my book of coupons, from which he tore several and
handed it back. Then he lifted his lantern and peered into the
compartment, saying, 'Is monsieur alone?'

"I turned to Wilhelmina.

"'He wants your ticket--give it to me.'

"'What's that?' demanded the guard.

"I looked anxiously at Wilhelmina.

"'If your father has the tickets--' I began, but was interrupted by
the guard, who snapped:

"'Monsieur will give himself the trouble to remember that I do not
understand English.'

"'Keep quiet!' I said, sharply, in French. 'I am not speaking to
you.'

"The guard stared stupidly at me, then, at my luggage, and finally,
entering the car, knelt down and peered under the seats. Presently he
got up, very red in the face, and went out slamming the door. He had
not paid the slightest attention to Wilhelmina, but I distinctly heard
him say, 'Only Englishmen and idiots talk to themselves!'

"'Wilhelmina,' I faltered, 'do you mean to say that that guard could
not see you?'

"She began to look so serious again that I merely added, 'Never mind,
I don't care whether you are invisible or not, dearest.'

"'I am not invisible to you,' she said; 'why should you care?'

"A great noise of bells and whistles drowned our voices, and, amid the
whirring of switch-bells, the hissing of steam, and the