After failure to construct good hide boats, two other craft, twenty-five and thirty-three feet long, were knocked together, and the crews launched above the rapids for the far Shining Mountains that lured like a mariner’s beacon.  Night and day, when the sun was hot, came the boom-boom as of artillery from the mountains.  The voyageurs thought this the explosion of stones, but soon learned to recognize the sound of avalanche and land-slide.  The river became narrower, deeper, swifter, as the explorers approached the mountains.  For five miles rocks rose on each side twelve hundred feet high, sheer as a wall.  Into this shadowy canon, silent as death, crept the boats of the white men, vainly straining their eyes for glimpse of egress from the watery defile.  A word, a laugh, the snatch of a voyageur’s ditty, came back with elfin echo, as if spirits hung above the dizzy heights spying on the intruders.  Springs and tenuous, wind-blown falls like water threads trickled down each side of the lofty rocks.  The water was so deep that poles did not touch bottom, and there was not the width of a foot-hold between water and wall for camping ground.  Flags were unfurled from the prows of the boats to warn marauding Indians on the height above that the voyageurs were white men, not enemies.  Darkness fell on the canon with the great hushed silence of the mountains; and still the boats must go on and on in the darkness, for there was no anchorage.  Finally, above a small island in the middle of the river, was found a tiny camping ground with pine-drift enough for fire-wood.  Here they landed in the pitchy dark.  They had entered the Gates of the Rockies on the 19th of July.  In the morning bighorn and mountain goat were seen scrambling along the ledges above the water.  On the 25th the Three Forks of the Missouri were reached.  Here the Indian woman, Sacajawea, recognized the ground and practically became the guide of the party, advising the two explorers to follow the south fork or the Jefferson, as that was the stream which her tribe followed when crossing the mountains to the plains.

[Illustration:  Packer carrying Goods across Portage.]

It now became absolutely necessary to find mountain Indians who would supply horses and guide the white men across the Divide.  In the hope of finding the Indian trail, Captain Lewis landed with two men and preceded the boats.  He had not gone five miles when to his sheer delight he saw a Snake Indian on horseback.  Ordering his men to keep back, he advanced within a mile of the horseman and three times spread his blanket on the ground as a signal of friendship.  The horseman sat motionless as bronze.  Captain Lewis went forward, with trinkets held out to tempt a parley, and was within a few hundred yards when the savage wheeled and dashed off.  Lewis’ men had disobeyed orders and frightened the fellow by advancing.  Deeply chagrined, Lewis hoisted an American flag as sign of friendship and