At seven next morning, before I was out of bed, my telephone rang, and Hecq once more spoke to me.
“I have been searching the papers, Sant,” he said, “and I have found out something that will interest you. Listen carefully. In the Petit Parisien five days ago there was an advertisement for the recovery of a lady’s gold trinket. I have it here. I’ll read it to you,” and he read:
Perdus Ou Trouvés.
Perdu Mét. Opéra Breloque Or.
Vialet 28 Marigny R. 100.
“Yes,” I said, “I hear you. But what has that to do with me?”
“Listen,” said Hecq. “There is nobody named Vialet at that address; we found that out at once. I have had nearly fifty of my people examining every advertisement in the Paris papers issued just before Heinrich began to display an interest in Royal Love Letters. Now we have found out that the advertisement I have just read to you conveys in cryptogrammic form the message, ‘Buy Royal Love Letters.’ It would take too long to explain it, but the paper containing that advertisement would be on sale in London the very day on which, according to Madame Gabrielle, Heinrich began to haunt the second-hand bookstalls on his peculiar quest. Rather curious, is it not?”
Curious it certainly was, and once more I found myself confronted with a further enigma. Why on earth should the book be advertised in cryptogrammic form in a French newspaper? How did Heinrich come to see the advertisement, and how did he know the key to the code? No doubt the paper had accepted the innocent-looking advertisement without the slightest suspicion that it was anything but the genuine announcement it purported to be. It was impossible to overlook the coincidence between the appearance of the advertisement and Blind Heinrich’s sudden deep interest in a forgotten book.
Next day I started out in search of a copy of Royal Love Letters. Of course I failed to get one: it had been out of print for years, as it had been published privately and comparatively few copies had been printed. However, I sent wires to some twenty provincial dealers in second-hand books, and at noon next day had a reply from a dealer in Birmingham, offering me a copy for four and sixpence. I wired the money, and next morning received the shabby little volume. Little did I realise what a dividend my investment of four shillings and sixpence was going to pay me!
On reading the book through, I found it was merely a monograph on the published love letters of various royal personages. It was as dull as the proverbial ditch-water, and I was not surprised at the difficulty both Heinrich and myself had experienced in securing copies: the wonder was that any had escaped the fire or the waste-paper basket. But the very fact made Heinrich’s interest in the book the more suspicious. It conveyed nothing to me, it is true, about Gotha raids on London, but did it convey anything to Heinrich, or was it the means of conveying anything from him to someone else?
I called up Madame Gabrielle on the ’phone, and after she had arrived and examined the volume, we went out to lunch at the Ritz. Across the table I told her of the curious advertisement in the Petit Parisien, whereupon she exclaimed:
“Why, Kristensten reads that paper regularly. I often see him with it. He goes down practically every column of it with his big reading-glass!”