“Well, I never saw any unrefined platinum,” Rogers told him. “And, of course, I can’t be certain, but what else could it be? No one took all that trouble to hide something that wasn’t pretty valuable.” “Sounds reasonable,” Bill told him. “Let’s get it back to camp and I’ll get my lab to working and we’ll soon know what it is,” Rogers told them. “We’ll take turns carrying it,” Bill proposed. “Help me get it up on my shoulder and I’ll take the first whack.” Changing the load at short intervals they made easy work of it and half an hour later Rogers was busy getting his chemicals and apparatus ready. “I’m not much of a chemist,” he told them, “But I studied up on this thing and don’t believe I’ll have much trouble.” “You better hadn’t,” Gordon warned him. “We don’t want to cart home a lot of worthless stuff.” “I’ll do the best I can. Believe me, I don’t want to get my hopes up again and get fooled. Now here’s the nitric acid. We’ll pour some out in this beaker and put a lump of the stuff in it and see if it has any action on it. If it’s any common metal it will dissolve. Where’s that little stove that uses that solid heat of yours? I want to warm the acid to make sure.” Gordon soon found the little stove and a moment later they were eagerly watching the experiment. “Not a sign of any action,” Gordon declared after five minutes had passed. “Which makes it look encouraging,” Rogers told him. “Now we’ll try some hydrochloric acid.” The result was the same with the latter acid and the hopes of all three were at fever heat as they watched the experiment. “Now we’ll try the aqua regia and see if that dissolves it,” Rogers told them as he mixed the two acids. “It should, shouldn’t it?” Bill asked. “If it’s platinum, yes.” How they all stared as he dropped a small lump into the mixture and how they cheered a moment later as they saw it slowly grow smaller and finally disappear. “I guess that settles it,” Bill cried. “Just a minute. There’s one more test to make to be sure,” Rogers told him as he diluted the mixture with some water. “If it’s platinum this solution of ammonium chloride, which I have in this bottle, will precipitate it.” Again they held their breath as he poured some of the solution into the beaker, but their joy was unbounded as they saw the dark colored precipitate thrown down and Rogers told them that it was the precious metal beyond the shadow of a doubt. “Now I reckon we can enjoy the flight home,” Gordon declared catching his cap on the back of his head as it descended from the height to which he had thrown it. “It’s dead certain that I’m going to,” Rogers assured him. “Boys, this means a lot to me.” “And I reckon we can use our share,” Bill grinned. “Well, I guess we’d better plan to spend the night here and get an early start in the morning,” Rogers suggested.