"By eleven o'clock, not only the sustaining but also the satisfying effect of the ounce of ham appeared to be exhausted; we were not only extremely hungry, but we were moving at a much slower pace. I represented to M. Longuet that it would be wise to have our déjeuner at once. But his dreadful middle-class instincts were too strong for us. He had the habit of a regular life so ingrained in him that he would not hear of déjeuner before noon. Also I marvelled at his power of endurance: I had never suspected that the manufacture of rubber stamps could endow a man with those muscles of steel. None the less we talked very little between eleven and noon. "That ounce of ham was one of the most delicious meals I have ever eaten. M. Longuet, who seemed in the course of our conversation to have caught some of my scientific spirit, timed the meal by my watch. It was a source of great satisfaction to him that he took from nine to eleven seconds longer over each mouthful than I did. After it we proceeded on our way with renewed vigour; and since I found that he was of the truly receptive type of mind, I found our conversation very enjoyable. "The afternoon was exactly like the morning. We walked, conversing about a dozen different subjects. The next morning was exactly like the last afternoon; and the days which followed were exactly like one another. The second and third days were the least comfortable. On those days the satisfying effects of our ounces of ham appeared to exhaust themselves more quickly. But after the third day I began to realise the great value of the discovery of M. Fletcher of the United States. Our appetites had become quite normal; an ounce of ham blunted them till the next meal. We were losing weight indeed, especially M. Longuet, whose waistcoat hung somewhat limply down in front. But the muscles of our legs appeared to have grown stronger; and undoubtedly our intellects had grown quicker and more alert. When we had exhausted my subjects, I learned from M. Longuet the process of making rubber stamps, with a thoroughness which fits me to embark at any moment on that career. I found that he was even quicker to acquire the knowledge which goes to the making of an able Commissary of Police. "It would indeed have been a very pleasant walking tour, thanks to that unlikeness of our natures which produces the most harmonious companionship, had it not been for the monotony of the scenery through which our way lay. The subterranean passages, illumined by our lamps, were sometimes vast, sometimes narrow, sometimes rounded like the naves of the cathedrals, sometimes square, angular, and mean, like the corridors of workhouses. But they presented no spectacle of great variety. When he had said, 'Look, stone! Look, clay! Look, sand!' we had said everything, because we had seen everything.