"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 cries of 'Paris! All out!' our train glided into the station.
"It was the professor who opened the door of our carriage. There he stood, calmly adjusting his yellow night-cap and drawing his dressing-gown closer with the corded tassels.