After breakfast I called the entire crew together. “Boys,” I said, “you know that we have many things unaccomplished. As yet we are only at the beginning of our task. Yesterday and the day before we were very successful, and now we have had a restful night. Being well rested, we are now cheerfully and confidently ready for another day’s work. To-day we are going to go through the so-called ‘Witch-Kettle.’ You all know what I mean, and you know also that this is not child’s play. The enemy there is keeping sharp lookout, but we will keep a better lookout. Others have gotten through before us. Consequently, we will also get through, if each one of you sticks to his post and does his duty as well as you all have done hitherto. This I expect from every man. And now—to the diving stations!” I went up to the tower. Shortly after the engineer reported from the “Centrale”: “All hands are at the diving station!” Consequently we were ready for our task. The day began—the most remarkable day of my life. “Arise!” The pump began to buzz. We now had to empty the ballast-tanks of the water which had been taken in to make the boat heavier, in order that, instead of being held down, we should begin to pull ourselves loose, and drift slowly upwards. Usually that manœuver was accomplished with the best of success, but not so to-day. The boat wabbled and “stuck,” as we used to say. It called to my mind the question which is often asked by laymen: “Are you never in fear of not being able to get up to the surface again?” We, of course, had no fear, but I knocked impatiently on the manometer to see if the register would not at last begin to move. “Nine hundred liters above the normal,” Krüger reported from the “Centrale.” It meant that we had pumped out of the boat nine hundred liters more than the normal quantity necessary to make the boat rise. “It seems as if we were fastened in a vise,” I joked, “but in accordance with the map there ought to be a sand bottom here.” “Now it loosens!” the engineer called out. Yes, the boat pulled loose all right—the hand on the manometer was rising—but it shot upwards on one side only. The stern arose but the nose remained fastened in the mud. “How confoundedly nasty,” I heard Gröning, who took care of the diving rudder, growl. Now the entire ballast shifted. We had to make the boat heavier in the stern, had to shift the ballast of the heretofore well-balanced boat and pump ballast water out of the bow to pour water into the stern tanks, in order to make the bow lighter and the stern heavier. After a few liters of water had exchanged places the boat changed her mind and again placed herself in a horizontal position. Then she arose quickly and satisfactorily, but showed a tendency to list toward the stern, until we, by a new shift of the ballast, had re-established the old conditions of equilibrium.