Through Kate Craigie, Gaylor discovered that Lady Hereward had believed her French maid Liane kept tryst with Ian Barr at the Tower. Why Lady Hereward had held this belief Kate did not know, but supposed she "must have heard something." Possibly Liane had been seen going to the Tower; in any case Kate knew that "her ladyship," who disapproved of Mr. Barr from the first, "because he was a dangerous socialist," suddenly became bitterly prejudiced against him, on account of an alleged flirtation between him and Liane.
Each day it began to appear more and more important to find Ian Barr, and the theory of the police was that he would be found through Miss Verney. Nevertheless, Nora had contrived to thwart the vigilance of her "shadow" on arriving in Paris, by posting a letter which he could not identify as hers.
He was there, on the spot, and watching, when she slipped something into a letter-box at the Gare du Nord. He had been given specimens of her handwriting, before he left England, and was granted the privilege of seeing each letter which the box contained. But not only was there no envelope or card addressed to Ian Barr, but there was no handwriting which resembled Miss Verney's. The half-French detective had an aggravating conviction that, if he could only open each of the many letters, he would find one from Nora Verney to Ian Barr; but he could not do that,
