"Even as this flashed into my mind, M. Longuet heaved a deep sigh, and stretched out his arms. He complained of pains about his body, bade me good-evening, and asked me where we were. I told him. He did not appear utterly dismayed by the information, but drawing a pocket-book from his pocket, he traced some lines which looked like a plan, showed them to me, and said:
"'My dear M. Mifroid, we are in the depths of the Catacombs. It's an extraordinary event; and how we are to get out I do not know. But the matter which fills my mind at this moment is really far more interesting, believe me, than falling into the Catacombs. I beg you to glance at this little plan.'
"He handed me the leaf from his pocket-book, on which I saw the following:
"He sneezed twice.
"'Oh, you have a cold,' said I, taking the paper.
"'Yes; I have had a bad cold since taking a somewhat long stroll one rainy night on the roofs of Gerando Street,' he said.
"I advised him not to neglect it. I must say that this quiet and natural conversation between two men in the depths of the Catacombs, a few minutes after their recovery from such an unexpected fall, gave me infinite pleasure. Having considered the lines on the paper, I asked the explanation of them; and M. Longuet told me the story of the disappearance of an express train and of the reappearance of a railway-carriage, which was by far the most fantastic I had ever heard. This man had desired to make an express disappear between A and B by sending it up a side-line H I, by shifting the points, and he had waited for it at K. But the train had neither appeared at A nor at K, that is to say, either to him or to anyone else. Next a railway-carriage had appeared to him at K; and presently that railway-carriage itself had disappeared. I could well have believed that this man, considering his past (the past of Cartouche!) and the story which he now told me, was mad, if he had not expressed himself so logically, and given me the most exact material details about the points, the switch, and all the facts of the case.
"Moreover, it is a matter of common experience that a madman always understands everything. But this man wanted to understand. I begged him to repeat the story. He said nothing. Twice I reiterated the request and still he said nothing. I was about to lose patience, when, grasping the fact that I had asked him something, he told me that now and then he was deaf for a few minutes.
"Since he had recovered his hearing, we returned to the problem of the express. He assured me that he would rather die ten times in the depths of the Catacombs than come out of them once without knowing what had become of this express. 'I do not wish,' he added, 'to lose the most precious thing in the world: my Reason.'