In March the men began boat-building, preparatory to resuming their journey. The batteau was too cumbrous for use toward the head waters of the Missouri, and it was to be sent back to St. Louis. To take its place, canoes were fashioned from green cottonwood planks. Cottonwood lumber is full of whims and caprices,--bending, twisting, cracking like brown paper, so as to be wholly unfit for ordinary carpentry; but there was no other material available. Six canoes were made to hang together somehow; and in these ramshackle structures, together with the two periogues, the party covered more than a thousand miles of the roughest water of the Missouri. Annoyance was to be expected. The boats were continually splitting, opening at the seams, filling, and swamping, so that much time was lost in stopping to make repairs and to dry the water-soaked cargoes. This was merely an inconvenience, not an obstacle. CHAPTER VI TO THE FALLS OF THE MISSOURI On the afternoon of April 7, 1805, winter quarters were abandoned. Of the original forty-five men two had been lost; but three recruits had been gained,--Chaboneau, his squaw Sacajawea, and their infant son, born in February. From Fort Mandan fourteen of the men returned to St. Louis in the barge, carrying documents, collections, and trophies, while thirty-two went onward, to be separated from their kind for almost eighteen months. On this day Captain Lewis wrote in his journal:-- "This little fleet altho' not quite so rispectable as those of Columbus or Capt. Cook, were still viewed by us with as much pleasure as those deservedly famed adventurers ever beheld theirs; and I dare say with quite as much anxiety for their safety and preservation. We were now about to penetrate a country at least two thousand miles in width, on which the foot of civilized man had never trodden; the good or evil it had in store for us was for experiment yet to determine, and these little vessells contained every article by which we were to expect to subsist or defend ourselves. However as the state of mind in which we are, generally gives the coloring to events, when the imagination is suffered to wander into futurity, the picture which now presented itself to me was a most pleasing one, entertaining as I do the most confident hope of succeeding in a voyage which had formed a darling project of mine for the last ten years, I could but esteem this moment of our departure as among the most happy of my life." April 26th they came to the mouth of the Yellowstone River, which enters the Missouri 1888 miles above St. Louis. They had had no adventure of moment; neither was there cause for immediate anxiety, save as they observed signs of the Assiniboins. From the tribes with whom they had talked at winter quarters, they had heard stirring tales of this cut-throat band, which had inspired the wish to pass unobserved through their country. This desire was fulfilled. There was no meeting with the Assiniboins.