Theophrastus, though he had with good reason made up his mind never again to be astonished by anything, was nevertheless astonished by the disappearance of the railway-carriage, with the earless head of Signor Petito waggling in the wind. With a melancholy air he walked down the little side-line, asking himself whether he ought to be more astonished by the disappearance of the carriage than by its sudden appearance. In truth, the suppression of the express was troubling his spirit deeply.

It seems to me that I, who know the secrets of the sandalwood box, have no right to give the explanation of this suppression before the hour at which Theophrastus learnt it himself, from a quite commonplace observation which the Commissary of Police, M. Mifroid, an earnest student of Logic from his earliest years, made to him in the Catacombs of Paris. At the same time, it is only fair to say that all the points in the problem are already in the possession of the reader, who can solve it himself, if indeed he has not already done so, without further delay. Theophrastus then, in a state of prostration, walked down the side-line, arrived at the bifurcation, examined the switch, thrust back the lever which he had thrust over, locked the padlock, and carried away, once and for all, the key which had been so carelessly left in it a few days before. He performed this action because he felt that it was only right; and he restored the switch to its place, because he felt that his reason could not stand another disappearance of the express.

Still melancholy, he reached the deserted station A. All the rest of the staff was absent on the search for the express; only the signal-man was on the look-out. Theophrastus questioned the signal-man, who could only say, as he pointed to the red arm of the signal:

"The express is signalled, but it does not come!"

"Was it really signalled from the last station?" said Theophrastus.

"Yes, sir, the station-master and all the staff of the last station saw the express go through it. They telegraphed it to us. Besides, sir, look at my little red arm! Look at my little red arm! And it is quite impossible that there should have been a wreck between the last station and this one. There is no bridge, sir, no viaduct, no works of art. Besides, just now I climbed to the top of that ladder against the big tank there. From it you can see the whole line right to the other station. I saw our people down the line, gesticulating, but I did not see the express!"

"Strange—very strange," said Theophrastus mournfully.

"Strange isn't the word for it! Look at my little red arm!"

"Inexplicable!" said Theophrastus gloomily.

"The most inexplicable thing in the world!" cried the signal-man.

"Not so: there is one thing even more inexplicable than an express which disappears with its engine and passengers without anyone being able to tell what has become of it," said Theophrastus in the same gloomy tone.

"What on earth's that?" said the signal-man, opening his astonished eyes wider than ever.

"Why, a railway-carriage without an engine which suddenly appears without one's being able to tell where it comes from.""What?" cried the signal-man.

"And which disappeared as suddenly as it appeared... You haven't by any chance seen a railway-carriage with a man looking out of the window pass this way?"

"You're laughing at me, sir!" said the signal-man with some heat. "You're exaggerating! Just because you don't believe the story of the express which has been signalled and does not come! But look, sir, look! Look at my little red arm!"

M. Longuet replied: "If you haven't seen the express, no more have I!"

He shrugged his shoulders bitterly and left the station. An idea had occurred to him: his misfortune was so utter and so irremediable that he was resolved to die... for others.

With a little astuteness the thing is practicable, even easy. Since he is dressed in the clothes of Signor Petito, nothing prevents him leaving his own clothes on the bank of the first river he comes to. This simple proceeding will constitute a formal act of suicide. Behold Marceline and Adolphe once more at peace!

On the bank of what river did M. Longuet lay his clothes? How did he re-enter Paris? These are matters of such little importance that he makes no mention of them in his memoirs. There is only one thing that is really important, the explanation of the disappearance of the express.

In the dull November sunset a workman was bricking up a hole in the roadway of a Paris square in the ancient Quarter d'Enfer. As he filled it he was singing the Internationale, the hymn of the advanced Labour Parties throughout the world.

This workman, a bricklayer, was with his comrades engaged in assisting in that perpetual occupation of modern municipalities, getting the streets up; and the street was up.

The municipal engineers had been making a new sewer through the Quarter d'Enfer with a patient disregard of the fact that under that quarter the Catacombs spread their innumerable tunnels. It was but natural that the bottom of the end of the excavation, in which they were laying the new sewer, should have fallen out, and that they should have been obliged to rest the pipes on railway sleepers cut in half. They were, however, at the end of their task: the hole at the bottom of the excavation, which ran right down to a passage of the Catacombs, had been nearly bricked up; and the aperture which remained could not have been much more than three feet across. As the bricklayer bricked it up, he sang the Internationale.

At the same hour, a few yards down the side of the square, M. Mifroid stood before the counter of a shop at which they sold electric lamps, and was buying half a dozen of them for his men. Each lamp was guaranteed to give forty-eight hours' light, though they were not much larger than cigar-cases. His lamps had been packed up; and he had just put his fingers through the loop of the string of the packet, when a little way down the counter he perceived a man, still young but with quite white hair, slipping several examples of these electric lamps into his pocket without paying for them. They would doubtless be quite as useful to a thief as a policeman. M. Mifroid, with his usual courage, sprang towards the man, crying, "It's Cartouche!"

He had recognised him owing to the fact that since the Calf's Revenge every Commissary of Police in Paris carried a portrait of the new Cartouche in his pocket. They owed them to Mme. Longuet herself and M. Lecamus, who had fled from the article in the evening paper to the nearest police-station, since they felt themselves bound, in the interests of humanity, to inform the police, somewhat tardily, of the bicentenary mental condition of Theophrastus.

Therefore M. Mifroid, who had had the further advantage of a passing acquaintance with Theophrastus in his home, recognised him at once.

Theophrastus, who had for some nights known the intentions of the police, when he saw M. Mifroid and heard his cry, said to himself, "It's time I was off!"

He bolted out of the shop; and the Commissary of Police bolted after him.

To return to our bricklayer, he sang the Internationale all the time. He was alone, because his comrades had gone round the corner to refresh themselves. He was at the chorus of the song; and it was the seventy-ninth time he had sung it since two o'clock in the afternoon. He raised his head towards Heaven and roared:

With his head turned to Heaven he did not see two shadows flying headlong, which, one after the other, fell through the hole; their cries were drowned in the volume of sound which poured from his lungs. They were the shadows of Theophrastus and of M. Mifroid pursuing him through the dusk. In their careless haste they fell clean through the street which was up. The bricklayer turned his head a little to the right and roared enthusiastically:

And he finished bricking up the hole. Singing the Internationale, he had performed the symbolic act of interring a policeman and a thief.