Hereby we had the line on which we stood, and must wait until the sun had changed its position to complete our calculations. The cutting point between the local lines would give our position. According to G.T.T. 5 h 47′ we took an observation in the morning which gave h--d by -33 nautical miles. These observation lines were constructed on the same chart, and the cutting point gave us our position 87° 47′ N. lat. and 13° W. long. Some days later we used these data as examples and re-calculated the same observations according to the method of St. Hilaire, and thereby found that our landing point lay on N. lat. 87° 43′ 2″ and W. long. 10° 19′ 5″. After our return our observations were again re-calculated according to absolutely exact astronomical formula by Cand. mag. R. Wesöe, under the guidance of Professor Schroeter. According to their calculations the most northerly point turned out to be N. lat. 87° 43′ and W. long. 10° 37′, the very spot where we had our first camp. During reconnoitering we went further north, but without taking observations. In addition to this Cand. mag. Wesöe calculated the positions as follows. I herewith give four: 1925. 22/5 N. lat. 87° 43′ Long. W. 10° 37′ 28/5 „ 87° 32′ „ „ 10° 54′ 6 29/5 „ 87° 31′ 8 „ „ 8° 3′ 9 12/6 „ 87° 33′ 3 „ „ 8° 32′ 6 These positions give an idea of the drift of the ice easterly and southerly. _Soundings_ We could see that it would be a matter of great and special interest if we could take soundings where we landed, and, discussing it fully, we came to the conclusion that we ought to be able to get sounding materials with a reasonable weight. We got into communication with the Behm Echolot Factory in Kiel, and all our difficulties were immediately brushed aside. After I had been to Kiel and talked over the matter with Herr Behm an excellent apparatus was made and placed gratis at our disposal. (As there were great depths in the district where we were to land, it was not necessary to take the depth to the nearest meter, but we could make an approximate registration. The weight of the whole sounding equipment, with cartridges for a number of charges, was cut down to a few kilograms. There was therefore no obstacle in the way of our taking it with us in the flying machine--and we could also have taken it with us even had we had to make a march towards land.) The principle was simply as follows. A watertight microphone was sunk about four meters down in the water of a crack in the ice. The microphone was attached by a line to an ordinary head-microphone, which the observer wore. At a distance of twenty-five to fifty meters from the observer a little charge was sunk under the surface which contained ten grams of trinol and was provided with a detonator. The charge was exploded by an electric spark. The observer set a stop-clock going when he heard the explosion, stopping it as soon as he heard the echo from the sea bottom.