"What? The lost mine that you and I stumbled upon in that terrible storm?" "That is the one, Peter." "Then, Tom Swift may as well return. I doubt if we can even locate the district where it was, and if we did find it, the winds blow so that even this magnificent ship could not weather the gales." "I guess he doesn't understand about my air glider," said Tom with a smile, when this was translated to him. "I wish I had a chance to put it together, and show him how it works." "Oh, it will work all right," replied Ned, who was very proud of his friend's inventive ability. "Now, what is the next thing to be done?" asked Tom, a little later that evening, when, supper having been served, they were sitting in the main cabin, talking over the events of the past few days. "I'd like to get on the track of that platinum treasure." "And we will do all in our power to aid you," said Ivan Petrofsky. "My brother and I owe much to you--in fact Peter owes you his life; do you not?" and he turned to him. "I do," was the firm answer. "Oh, nonsense!" exclaimed Tom, who did not like to be praised. "I didn't do much." "Much! You do not call taking me away from that place--that sulphur mine--that horrible prison barrack with the cruel guards--you do not call that much? My friend," spoke the Russian solemnly, "no one on earth has done so much for me as you have, and if it is the power of man to show you where that lost mine is, my brother and I will do so!" "Agreed," spoke Ivan quietly. "Then what plans shall we make?" asked Tom, after a little more talk. "Are we to go about indiscriminately, or is there any possible way of getting on the trail?" "My brother and I will try and decide on a definite route," spoke Ivan Petrofsky. "It is some time since I have seen him, and longer since we accidently found the mine together, but we will consult each other, and, if possible make some sort of a map." This was done the next day, the present maps aboard the Falcon being consulted, and the brothers comparing notes. They began to lay out a stretch of country in which it was most likely the lost mine lay. It took several days to do this, for sometimes one brother would forget some point, and again the other would. But at last they agreed on certain facts. "This is the nearest we can come to it," said Ivan Petrofsky to Tom. "The lost platinum mine lies somewhere between the city of Iakutsk and the first range of the Iablonnoi mountains. Those are the northern and southern boundaries. As for the western one, it is most likely the Lena river, and the eastern one the Amaga river. So you see you have quite a large stretch of country to search, Tom Swift." "Yes, I should say I had," agreed the young inventor. "But I have had harder tasks. Now that I know where to head for I'll get there as soon as possible." "And what will you do when you arrive?" asked Ned.