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Historical Background

Abandonment of the "Experiment"

While the portage was being made, progress was registered in another important preparation necessary before the journey could continue upriver. The iron-framed "Experiment," Lewis' pet project, which had been manufactured at Harpers Ferry for use on the Upper Missouri and brought all the way from Pittsburgh, had to be assembled and covered as a replacement for the white pirogue. The former was one of the first items portaged so that assembly work could begin. Taking Shields, Gass, and Joseph Field with him to the upper portage camp, Lewis on June 23 had eagerly begun work and, on July 2 when the move was completed, everyone pitched in to help. Two days later, July 4, was as usual cause for celebration; the last of the whisky was consumed. But at least the portage had been completed.

Once the 36-foot-long iron frame was assembled and timber struts put in place, they were covered with elk and buffalo skins that were sewn together. The method of caulking the seams posed a serious problem. No tar or pitch was available, so Lewis improvised with a mixture of pounded charcoal, buffalo tallow, and beeswax. Launched on the 9th, the boat floated like a "perfect cork," but by that night most of the caulking had separated from the skins, which left open seams. The "mortifyed" as well as depressed Lewis, because the season was late and most of the buffalo had departed, decided that any more caulking experiments would probably be useless and decided to abandon his "favorite boat." Failure to bring along suitable caulking material represented the one major error in logistical planning.

Abandonment of the "Experiment" necessitated the expenditure of 5 additional days to construct two dugout canoes to replace it and supplement the six other canoes. Between the 10th and the 14th, at a site about 8 miles by land or 23 miles by water above the upper portage camp, Clark and a crew of 10 men found cottonwoods of large enough size along the Missouri to build the canoes. Both were 3 feet wide, one 25 and the other 33 feet long. Meantime, the frame of the "Experiment" had been disassembled and buried near the upper portage camp, as well as the wagon wheels. Supplies that were cached included all the plant specimens acquired since leaving Fort Mandan, a few bearskins, various papers, and some medicines.

On the 14th the rest of the expedition moved up to the canoe-building camp from the upper portage camp. The next morning, the entire complement set out once again.

View from the north bank of the Missouri River looking toward the mouth of modern Belt Creek, known to the explorers as Portage Creek. They pulled their canoes about a mile up it, carried them to the high plains at the top of the bluffs, and then laboriously transported them on crude wagons to the upper portage area. The above scene has changed little over the years except that a number of upstream dams now seasonally restrict the water flow. (National Park Service (Appleman, 1964).)

BY this time, the two captains were becoming highly apprehensive about meeting the Shoshonis. The anxiety experienced even before arrival at the Great Falls had been compounded by the month required to portage around them and build the two canoes to replace the "Experiment." More than 3 months had elapsed since departure from Fort Mandan and the Rockies had barely been penetrated. How long it would take to reach the Pacific could not even be estimated, but it was certain that the trip there and back to Fort Mandan or even to the Great Falls could not be made that season.

The difficulties at the portage had already forced a change of plans. Lewis and Clark decided not to dispatch a detachment to St. Louis from the Great Falls as they had planned at Fort Mandan. The most perilous part of the journey lay ahead. The Shoshonis and other tribes might be hostile. The morale of those who would have to remain would be lowered. Every last man would be needed in the days that were to follow.