Pressing the transmitter fronts with the carbon capsules against the paper and the glass on the picture he mounted them so that the paper and glass acted as a large diaphragm to collect all the sounds in the room.

"The size of this glass diaphragm," he explained as we gathered around in intense interest at what he was doing, "will produce a strikingly sensitive microphone action and the merest whisper will be reproduced with startling distinctness."The boy brought the wire up and also the news that the couple in whose room we were had very nearly finished luncheon and might be expected back in a few minutes.

Kennedy took the tiny wires, and after connecting them hung up the picture again and ran them up alongside the picture wires leading from the huge transmitter up to the picture moulding.Along the top of the moulding and out through the transom it was easy enough to run the wires and so down the hall to a vacant room, where Craig attached them quickly to one of the old telephone receivers.

Then we sat down in this room to await developments from our hastily improvised picture frame microphone detective.

At last we could hear the elevator door close on our floor.Amoment later it was evident from the expression of Kennedy's face that some one had entered the room which we had just left.He had finished not a moment too soon.

"It's a good thing that I didn't wait to put a dictograph there,"he remarked to us."I thought I wasn't reckoning without reason.

The couple, whoever they are, are talking in undertones and looking about the room to see if anything has been disturbed in their absence."Kennedy alone, of course, could follow over his end of the telephone what they said.The rest of us could do nothing but wait, but from notes which Craig jotted down as he listened to the conversation I shall reproduce it as if we had all heard it.There were some anxious moments until at last they had satisfied themselves that no one was listening and that no dictograph or other mechanical eavesdropper, such as they had heard of, was concealed in the furniture or back of it.

"Why are you so particular, Henri?" a woman's voice was saying.

"Louise, I've been thinking for a long time that we are surrounded by spies in these hotels.You remember I told you what happened at the Vanderveer the night you and Madame arrived? I'm sure that waiter overheard what Gonzales and I were talking about.""Well, we are safe now anyhow.What was it that you would not tell me just now at luncheon?" asked the woman, whom Kennedy recognised as Madame de Nevers's maid.

"I have a cipher from Washington.Wait until I translate it."There was a pause."What does it say?" asked the woman impatiently.

"It says," repeated the man slowly, "that Miss Lovelace has gone to Washington.She insists on knowing whether the death of Marie was a suicide or not.Worse than that the Secret Service must have wind of some part of our scheme, for they are acting suspiciously.Imust go down there or the whole affair may be exposed and fall through.Things could hardly be worse, especially this sudden move on her part.""Who was that detective who forced his way to see her the night they discovered Marie's body?" asked the woman."I hope that that wasn't the Secret Service also.Do you think they could have suspected anything?""I hardly think so," the man replied."Beyond the death of Madame they suspect nothing here in New York, I am convinced.You are sure that all her letters were secured, that all clues to connect her with the business in hand were destroyed, and particularly that the package she was to deliver is safe?""The package? You mean the plans for the coaling station on the Pacific near the Canal? You see, Henri, I know.""Ha, ha, - yes," replied the man."Louise, shall I tell you a secret? Can you keep it?""You know I can, Henri."

"Well, Louise, the scheme is deeper than even you think.We are playing one country against another, America against - you know the government our friend Schmidt works for in Paris.Now, listen.

Those plans of the coaling station are a fake - a fake.It is just a commercial venture.No nation would be foolish enough to attempt such a thing, yet.We know that they are a fake.But we are going to sell them through that friend of ours in the United States War Department.But that is only part of the coup, the part that will give us the money to turn the much larger coups we have in the future.You can understand why it has all to be done so secretly and how vexatious it is that as soon as one obstacle is overcome a dozen new ones appear.Louise, here is the big secret.By using those fake plans as a bait we are going to obtain something which when we all return to Paris we can convert into thousands of francs.

There, I can say no more.But I have told you so much to impress upon you the extreme need of caution.""And how much does Miss Lovelace know?"

"Very little - I hope.That is why I must go to Washington myself.