"I am not mistaken," I said, and examining the map, I added, "We have passed Cape Portland, and those fifty leagues bring us under the wide expanse of ocean." "Under the sea," my uncle repeated, rubbing his hands with delight. "Can it be?" I said. "Is the ocean spread above our heads?" "Of course, Axel. What can be more natural? At Newcastle are there not coal mines extending far under the sea?" It was all very well for the Professor to call this so simple, but I could not feel quite easy at the thought that the boundless ocean was rolling over my head. And yet it really mattered very little whether it was the plains and mountains that covered our heads, or the Atlantic waves, as long as we were arched over by solid granite. And, besides, I was getting used to this idea; for the tunnel, now running straight, now winding as capriciously in its inclines as in its turnings, but constantly preserving its south-easterly direction, and always running deeper, was gradually carrying us to very great depths indeed. Four days later, Saturday, the 18th of July, in the evening, we arrived at a kind of vast grotto; and here my uncle paid Hans his weekly wages, and it was settled that the next day, Sunday, should be a day of rest. CHAPTER XXV. DE PROFUNDIS I therefore awoke next day relieved from the preoccupation of an immediate start. Although we were in the very deepest of known depths, there was something not unpleasant about it. And, besides, we were beginning to get accustomed to this troglodyte [1] life. I no longer thought of sun, moon, and stars, trees, houses, and towns, nor of any of those terrestrial superfluities which are necessaries of men who live upon the earth's surface. Being fossils, we looked upon all those things as mere jokes. The grotto was an immense apartment. Along its granite floor ran our faithful stream. At this distance from its spring the water was scarcely tepid, and we drank of it with pleasure. After breakfast the Professor gave a few hours to the arrangement of his daily notes. "First," said he, "I will make a calculation to ascertain our exact position. I hope, after our return, to draw a map of our journey, which will be in reality a vertical section of the globe, containing the track of our expedition." "That will be curious, uncle; but are your observations sufficiently accurate to enable you to do this correctly?" "Yes; I have everywhere observed the angles and the inclines. I am sure there is no error. Let us see where we are now. Take your compass, and note the direction." I looked, and replied carefully: [1] tpwgln, a hole; dnw, to creep into. The name of an Ethiopian tribe who lived in caves and holes. ??????, a hole, and ???, to creep into. "South-east by east." "Well," answered the Professor, after a rapid calculation, "I infer that we have gone eighty-five leagues since we started." "Therefore we are under mid-Atlantic?" "To be sure we are."