It is commonly held that while the Corps of Discovery wintered at Fort Mandan the Captains learned from the Indians the Missouri River had a single great waterfalls a short ways from where it entered the Rocky Mountains. The Captains then reasoned a short, maybe half-day, portage would be required to bypass the falls before continuing on to the headwaters of the Missouri. However, the truth as Lewis discovered was a series of five waterfalls would need to be overcome with a portage of no less than thirteen miles.
Explanations for the Indians not knowing about the other four waterfalls lie with the explanation for their lack of knowledge of the Marias River. When traveling overland by horseback from their homeland the Mandans or Hidatsa would follow the river to about the mouth of the Judith then continue on west as the river turns north then back to the southwest forming a large arc. They would rejoin the Missouri near the natural ford just below the Sun (Medicine) River. At this location they would hunt buffalo, deer, elk, etc. in the area from the Sun River downstream to the first waterfalls (Lewis’ Upper Pitch, now called Black Eagle Falls). By making an overland journey they would have missed the Marias as it joins the Missouri in the arc. For the same reasons they would have missed the other four waterfalls since they are all downstream from the one they knew about.
But is that the real story? Maybe there is a different theory that better explains the situation. If we go back and re-examine the facts we may find that a different conclusion is possible. As York says in Frank Walker’s book When Winter Comes, “There be two sides to every story an then there be the truth.”
Lewis described the first falls he arrived at on June 13, 1805 and says below it is a three acre bottom with several Indian lodges. Consequently we know some Indian group knew about these falls; we do not know exactly who they were. He also said that for three miles below the falls “the river was one continued scene of rapids and cascades.” The next day he walked upriver from the Great Falls to the Sun River. He described the river for eight miles as continuous rapids and small cascades to the Upper Pitch, the waterfalls that is the farthest upriver and just a short distance below the mouth of the Sun River. He described in detail four waterfalls-Great Falls, Crooked Falls, Rainbow Falls, Upper Pitch-and mentioned another small one, Colter Falls. He also recorded that the Indians said the Medicine (Sun) River fell into the Missouri just above the falls. They must have said something about an eagle’s nest below the falls since Clark refers to such when he says on June 14, “Capt L informs the (party) that those falls in part answer the description given of them by the Indians; much higher; the eagles nest which they describe is there.” What we get from Lewis’ description of the river is about eleven mile stretch of rapids cascades etc. that is not really very good for water craft to travel on. It would all have to be bypassed with an overland route.
Since it appears we have a conflict we can not necessarily take the journal keepers writings literally or as complete facts of the situation and do no further examinations of other sources. Lowell Schake writes in his book, “La Charrette: village gateway to the American West” the following note of caution to understanding journals of early explorers: “Were it not for the journals faithfully maintained by various expedition members and travelers, our knowledge of western frontier events would be greatly diminished from what they are. Many who took the time at the end of an exhaustive day’s work were not greatly disposed to write. Often their entries were lacking in some essential detail to include confusion over dates. They did their best under adverse conditions; there were ample excuses not to write. They recorded many things. Most would record what impressed or amused them, while others recorded aspects of their ventures for a perceived readership.” So let’s look a little further into this matter.
None of the journal keepers specifically said the Indians told them there was a single waterfall. Clark could have been confused as to where Lewis said he saw the eagle’s nest. Could Lewis have meant below the “Upper Pitch” while Clark thought he meant below the “Great Falls”? This is the only mention of an eagle’s nest below the Great Falls while sightings of an eagle’s nest below the Upper Pitch continued for another 70 years. Accepting this as probable clears part of the confusion surrounding what the Expedition knew about the falls.
If Indians had camped below the Great Falls as Lewis reported on June 13, simple logic tells us they would surely know the area of the other falls. This is not a large area for mounted hunters to cover.
Another piece of the puzzle is that from reading the journals we find that in June when the Expedition was in the area of the falls they saw large herds of animals all over, not just in the area of the natural ford near the mouth of the Medicine (Sun) River. By late July the herds had all moved on to feeding grounds much farther south. Hunters who depend on their knowledge of game animals for their food supply would know these patterns of when and where to find their game.
A final set of considerations is how the Expedition communicated with the Indians. Common to people who speak different languages is a mixture of words and gestures that will normally be adequate for everyone to get a general understanding of what’s being said. However, details are frequently omitted, or misunderstood, as are cultural uniquenesses. Communicating with someone when there is no common language is like playing charades. Consequently it would have been easy for the Expedition to get the concept of waterfalls but miss the detail of how many or distinguish between waterfalls and bad rapids.
And finally remember this was all done orally so the Expedition could not take a written document prepared by the Indians and spend days or weeks studying it so be sure to get all the details they might have missed during the meeting. They could only depend upon notes they may have written themselves during their talks and hope they understood what had been spoken.
My logic tells me that since several tribes regularly hunted this area, including the Hidatsa, they knew the area of the Great Falls well, particularly since it is rather unique to have waterfalls on a river running through the prairie. So the lack of passing on to the Expedition the fact of a series of five waterfalls instead of a single falls was not lack of knowledge but a result of incomplete communications between two groups who spoke different languages.