It was six o'clock on the following evening.

In a tiny room high up in the HÔtel Malmaison, above the servants' quarters, and on the roof, indeed—for the valet of Monsieur Montoyer was asthmatic and must breathe the freshest air possible—Emile Deschamps was standing.

The blinds were drawn, the room was lit by candles stuck in bottles, and presented the air more of a workshop than a bedroom.

The bed was littered with pliers, coils of insulated wire, strips of thin india-rubber, and a tube of vulcanised paste for making joints. Upon a large mahogany table close to the window stood a complicated apparatus.

At one end there was a battery of Leyden jars, then came the intricate induction coil upon a polished stand, its brass terminals glittering in the light of the candles. Beyond was the interrupter magnet and beyond that again the stout "seven-sixteens" wire which led to the electric light casing in the wall, where the hotel current had been tapped to take the place of a dynamo.

Upon that part of the table where the interrupter magnet was, there was an apparatus which in some degree resembled the keyboard of a typewriter. No letters were on these keys however. They bore numbers only, from one to thirty-six, with the addition of a nought to represent zero.

Deschamps, in list slippers, was walking nervously up and down the room. Perspiration shone upon his face. His eyes had a fixed introspective stare. He was obviously in a state of the highest possible tension.

Up and down the room he paced, like some caged animal, and every now and again he rolled a cigarette, lit it, and inhaled a few whiffs of pungent blue smoke, and threw it away. Now and then he poured himself out a cup of strong coffee from a little cafetiÈre which stood upon the mantelshelf. On the hearth burned a small glowing fire of the mountain wood and fir cones which are used upon the Riviera, and beside it stood a soldering "iron" of copper, a file, and a bottle of zinc chloride solution.

Deschamps looked at his watch.

"Basil is late," he muttered to himself, mopping his brow as he did so with a very dingy handkerchief. "Mon Dieu, if only this were over!"

He resumed his walk, thinking deeply, checking off each incident of the great adventure, the great fight of science against the precautions and wariness of the most complete and cunning organisation in Europe.

The plans of the partners had been altered and modified. As the preparations continued in Paris and the scheme was discussed a thousand times, and with an infinity of detail which crystallised more and more into definiteness, the most important thing that was at length determined on—and the Carnet brothers had been in thorough agreement—was that play should only last for one night. The confederates had thought that phenomenal winnings, protracted over two or three days, would inevitably give rise to suspicion. These suspicions would, in all human probability, be absolutely wide of the real mark. But, at any rate, they would be certain to result in the wheel at the table where Monsieur Charles Edouard Montoyer made his colossal coups being changed for another.

It was resolved, therefore, that Basil should play, with the aid of the unseen electric influences, for one evening only. The whole thing had been worked out, and it had been found that it would be easy, if nothing went wrong, for him to win an enormous sum even within a few hours. Directly that was accomplished Deschamps would pack his apparatus and return to Paris. Basil would remain at Monte Carlo for a few days and venture a few small sums to avoid suspicion. After that he would rejoin his friend.

There was a low knock at the door, an interval of silence, and then five more distinct taps.

Deschamps knew that Basil was without, and he quietly unlocked the door and let in his friend.

Basil, tall, foreign looking, and in the most scrupulously chosen evening dress, entered the dingy little bedroom with its litter of machinery and tools. The door was locked behind him and the partners were alone together.

Deschamps started. "Mon Dieu!" he said, "your sang froid is admirable. You are—how do you call it?—cool as a cucumber. Froid comme un concombre. Look at me; I tremble all over, moi!"

Basil shrugged his shoulders. "What is the use?" he said briefly. "I have been nervous enough up to the present, but now the moment has arrived I have just got to keep cool. The biggest strain is on me, and if I fail now all our plans are over and it means"—he threw out his hands with a foreign gesture—"well, we won't talk of what it means."

"You are marvellous!" said the excitable little Frenchman. "You have no tremor, no compunction."

Basil shook his head. "I am strung up to go through with it," he answered, "and take what comes—fortune or prison. As for compunction, it seems to me a good deed to rob the proprietors of this hell if one can, considering all the stories I have heard during the few hours I have been here, and the evil passions I have seen displayed on all sides. And, moreover, we do it for the sake of science, to confer an inestimable benefit on the world!"

"Bien," Deschamps answered. "Now, have you got the card absolutely safe? Let's compare it with mine for the last time."

From out of his pocket Basil drew an oblong slip of card. Upon it, written in a cypher invented by himself and Deschamps, in which they had perfected themselves during the last week or two, were a series of numbers. Above each number was marked the time—9:5, 9:15, etc., etc.

They went through the cards together finding them to correspond in every detail.

"And now for the watches," said Deschamps. From a kit bag in the corner of the room he produced a leather case, containing two handsome gold chronometers. "I have kept them there until now," he said, "in order that they might not become magnetised by the electric work I have been doing."

With the utmost care and nicety he adjusted the timepieces so that they did not vary, one from the other, by a single second. Then he gave one chronometer to Basil, and returned the other to the portmanteau.

"I have been playing all the day," Basil said, "with the hundred and fifty louis we reserved for that. Sometimes I lost, sometimes I won. But I spread my money about with supreme indifference. Always I put down a maximum stake, and I played upon a number. Of course, I lost many times, but I am sure I gave the desired impression to the croupiers at our table where the marked wheel is, that I was a wealthy gambler indifferent as to whether I won or lost. Towards the end I had a stroke of luck. I had put nine louis on 7, and 7 turned up. So that I won 6,300 francs. I had heard that the rule forbidding all tips to the croupiers had been recently abrogated; so that I feed the men in my neighbourhood magnificently. I shall get a seat at our table all right if I am punctual when the Casino opens for the evening play."

"And what are you going to do now?" Emile asked anxiously. "Will you stay here with me?"

"I don't think so, mon ami," Basil returned. "We have worked out every possible detail. The more we talk about it, the more nervous we shall become. I shall go to my room, have a little fish and a single glass of wine, and then stroll round the gardens in the fresh night air until it is time to go in." He held out his hand. "Good luck, old fellow!"

Deschamps grasped it and nodded, too full of emotion and excitement to answer.

Then Gregory quietly left the room and descended to his own.

As he walked down the passage he heard the click of the lock being shot into its place and knew that Deschamps would be alone with his machinery till midnight.