"Who is the next one you have on your list?" asked Captain Lewis. "I count considerably on your natural sagacity to help in running this traitor to earth. You boys have learned pretty well how to judge men from their actions and looks, rather than from their fair speech. Tell me the other names, please, Dick." "Fields is the second man. I base my right to include him in the group from the fact that there was a time when my cousin, here, and Fields had hot words over something the trapper had been doing in the village, and which Roger took him to task for. Since that time they have been on speaking terms, but I do not think Fields likes us over much." "I should regret very much to learn that Fields had turned traitor, for I have in the past been ready to trust him to any extent," remarked Captain Lewis. "The third and last man is Andrew Waller," continued Dick. "Now, we have never had a word with Andrew except in the best of ways. We have always looked on him as a loyal friend, and faithful to the trust you put in him. It has only been of late that both of us noticed that Andrew seems to try to avoid us, and when we do meet face to face he lets his eyes drop." "That is indeed a suspicious fact," commented the other, quickly. "If money has tempted him to play the part of a traitor it is easy to understand how he cannot look you squarely in the eye. Conscience flays him every time he sees you near by. I shall certainly bear in mind what you have told me, and in due time results may spring from keeping a close watch on the movements of these three men." With that Captain Lewis left the boys, but they felt sure he would not allow the matter to drop. The man whom President Jefferson had personally selected to manage this big enterprise, and who had been his own private secretary, was accustomed to getting results whenever he attempted anything. It was on the following morning that camp was broken, and the expedition once more started forward--down the Yellowstone to the Missouri, and up that muddy stream again. That was an event of vast importance in the lives of those daring souls who were thus venturing to plunge deeper into the mysteries of the country that up to then had never known the imprint of a white man's foot. Although filled with exultation, as were the rest of the travelers, Dick and his cousin looked back to see the last of the weird Mandan village which had long been a source of delight to their eyes. It was with considerable regret that they took their farewell view of the painted lodges, as well as the Indian cemetery on the side of the hill, where all those platforms, bearing their mummy-like burdens wrapped in buffalo hides, told of superstitions that were a part of the Mandan nature.