"There is none like it in all the world," went on the Russian, "and perhaps there never can be any more. I have only a small supply. But in Siberia--in the lost mine--there is a large quantity of it, as pure as this, needing only a little refining. "Can't we get some from there?" asked the young inventor eagerly. "I should think the Russian government would mine it, and export it." "They would--if they could find it," said Ivan Petrofsky dryly, "but they can't--no one can find it--and I have tried very hard--so hard, in fact, that it is the reason for my coming to this country--that and the desire to find and aid my brother, who is a Siberian exile." "This is getting interesting," remarked Ned to Tom in a low voice, and the young inventor nodded. "My brother Peter, who is younger than I by a few years, and I, are the last of our family," began Mr. Petrofsky, motioning Tom and Ned to take chairs. "We lived in St. Petersburg, and early in life, though we were of the nobility, we took up the cause of the common people." "Nihilists?" asked Ned eagerly, for he had read something of these desperate men. "No, and not anarchists," said Mr. Petrofsky with a sad smile. "Our party was opposed to violence, and we depended on education to aid our cause. Then, too, we did all we could in a quiet way to help the poor. My brother and I invented several life-saving and labor-saving machines and in this way we incurred the enmity of the rich contractors and government officials, who made more money the more people they could have working for them, for they made the people buy their food and supplies from them. "But my brother, and I persisted, with the result that we were both arrested, and, with a number of others were sent to Siberia. "Of the horrors we endured there I will say nothing. However, you have probably read much. In the country near which we were quartered there were many mines, some of salt and some of sulphur. Oh, the horrors of those mines! Many a poor exile has been lost in the windings of a salt mine, there to die miserably. And in the sulphur mines many die also, not from being lost so much as being overcome by stifling gases. It is terrible! And sometimes they are purposely abandoned by their guides, for the government wants to get rid of certain exiles. "But you are interested in platinum. One day my brother and I who had been sent to work in the salt mines, mistook a turning and wandered on and on for several miles, finally losing our way. We had food and water with us, or we would have perished, and, as it was, we nearly died before we finally found our way out of an abandoned opening. "We came out in the midst of a terrible snowstorm, and wandered about almost frozen. At last we were found by a serf who, in his sled, took us to his poor cottage. There we were warmed and fed back to life.