In 1881 also the International Polar Conference attempted to establish a chain of stations around the pole as far north as possible. The United States and several of the European nations were represented in the organization. Two expeditions were sent out by the United States; one at Point Barrow, under Lieutenant Ray, the other at Lady Franklin Bay, opposite the Greenland coast, in latitude 81 deg. 40'. The latter was in charge of Lieutenant, now General Greely. In a sledge journey along the north coast of Greenland, Lockwood and Brainard reached the latitude of 83 deg. 24'. The observations of Greely and Ray added not a little knowledge concerning the meteorology and tides of the arctic regions. The sledge journey of Lockwood and Brainard practically established the fact that Greenland is an island. Of all attempts to reach the pole, the most daring was that adopted by S. A. Andree, a Swedish explorer. Andree had been to the polar regions before, and being something of an aeronaut, believed that he could reach or pass over the pole in a balloon. In carrying out his plan he had constructed a monster balloon capable of floating in the air thirty days, due allowance being made for the daily escape of gas by permeation through the envelope. This balloon, with necessary accessories, was shipped to Danes Island, one of the Spitzbergen group. Everything being ready July 11, 1897, Andree set forth on his perilous trip accompanied by two companions. The balloon carried a load of about five tons, including food, clothing, ballast, scientific instruments, and men. On being let loose the balloon arose six hundred feet, and then descended to the surface of the sea owing to the entanglement of the guide ropes and ballast lines. Three heavy guide ropes nine hundred feet long were used, to which were attached eight ballast lines two hundred and fifty feet long. The ropes were cut and ballast was thrown out, when the balloon again rose and the wind bore it away over a mountainous island one thousand five hundred feet high. In an hour it had passed below the northeastern horizon. Three message buoys were dropped on the day of Andree's departure, reporting fine weather, all well, and altitude eight hundred and twenty feet; from that time on no traces of the daring unfortunates have ever been found.