And here it may be said that neither of them was ever to know who sent that brief effective message to the magistrate, nor were they ever to know the nature of its contents.
The men were examining the car when they came up. No one was near. There was no one to tell how it came to be there nor whither its unknown driver had gone. It stood close to the curb and the engine was throbbing, proof in itself that some one had but recently deserted his post as guardian.
"The obliging man-hunters," suggested Robin in reply to a low-voiced question.
"Or your guardian angel, the great Gourou!" she said, frowning slightly. "By the way, Mr. Schmidt, do you expect to be under surveillance during your stay at Interlaken?"
There was irony in her voice. "Not if I can help it," he said. "And you, Miss Guile? Is it possible that two of the best detectives in Paris are to continue treading on your heels all the time you are in Europe? Must we go about with the uncomfortable feeling that some one is staring at us from behind, no matter where we are? Are we to be perpetually attended by the invisible? If so, I am afraid we will find it very embarrassing."
They were in the car now and proceeding at a snail's pace toward the Arc de Triomphe. Her eyes narrowed. He was sure that she clutched her slim fingers tightly although, for an excellent reason, he was not by way of knowing. He was rapturously watching those expressive eyes.
"I shall put a stop to this ridiculous espionage at once, Mr. Schmidt. These men shall be sent kiting—I mean, about their business before this day is over. I do not intend to be spied upon an instant longer."
"Still they may have been instruments of providence to-day," he reminded her. "Without them, we might now be languishing in jail and our spotless names posted in the Place de l'Opera. Bedelia Guile and Rex Schmidt, malefactors. What would your father say to that?"
She smiled—a ravishing smile, it was. His heart gave a stupendous jump. "He would say that it served me right," said she, and then: "But what difference can it possibly make to you, Mr. Schmidt, if the detectives continue to watch over me?"
"None," said he promptly. "I suppose they are used to almost anything in the way of human nature, so if they don't mind, I'm sure I sha'n't. I haven't the slightest objection to being watched by detectives, if we can only keep other people from seeing us."