One of the most difficult aspects of Lewis and Clark’s cross-continental journey was figuring out how to transport the tons of goods and supplies they had brought. As transportation conditions changed along the river, the logistics of handling so much baggage on land became impractical or downright impossible. At three major points along the route, Lewis and Clark were forced to build underground caches to store ammunition, supplies, or other articles too big and bulky to transport. They built three major caches in all during the course of the expedition, all in present-day Montana.
The use of cache pits for storage would have been well-known to the Corps of Discovery. White settlers and Native Americans alike dug carefully constructed holes to store food for the winter, and fur trappers often dug caches to hide animal pelts until they could transport them somewhere to be sold. A cache pit functioned something like a cellar. Cache pits were typically six to eight feet deep and shaped like a jug, with a wide bottom and narrow mouth. They were often lined with animal hides and grasses, and shored up with sticks to prevent the cache from collapsing onto the food or goods stored inside.
Lewis and Clark built their first cache in early June 1805, on an island near the confluence of the Marias and the Missouri Rivers, a spot known as “Decision Point.” At that time, the Captains were facing the difficult dilemma of whether the muddy north fork or swift-flowing south fork was the true Missouri River. Choosing to follow the less navigable south fork, Lewis and Clark decided to leave the red pirogue and some of the heavier baggage behind. On June 9, 1805, Lewis wrote in his journal:
We determined to deposite at this place the large red perogue all the heavy baggage which we could possibly do without and some provision, salt, tools powder and Lead &c with a view to lighten our vessels and at the same time to strengthen their crews by means of the seven hands who have been heretofore employd. in navigating the red perogue; accordingly we set some hands to diging a hole or cellar for the reception of our stores. these holes in the ground or deposits are called by the engages cashes; on enquiry I found that Cruzatte was well acquainted this business and therefore left the management of it intirely to him.
The next day, Lewis reported that the deed was done. “In order to guard against accedents we thout it well to conceal some ammunicion here and accordingly buryed a tin cannester of 4 lbs. of powder and an adequate quantity of lead near our tent; a cannester of 6 lbs. lead and an ax in a thicket up the S. Fork three hundred yards distant from the point. we concluded that we still could spare more amunition for this deposit Capt. Clark was therefore to make a further deposit in the morning, in addition to one Keg of 20 lbs. and an adequate proportion of lead which had been laid by to be buryed in the large Cash. we now scelected the articles to be deposited in this cash which consisted of 2 best falling axes, one auger, a set of plains, some files, blacksmiths bellowses and hammers Stake tongs &c. 1 Keg of flour, 2 Kegs of parched meal, 2 Kegs of Pork, 1 Keg of salt, some chissels, a cooper’s Howel, some tin cups, 2 Musquets, 3 brown bear skins, beaver skins, horns of the bighorned anamal, a part of the men’s robes clothing and all their superfluous baggage of every discription, and beaver traps.— we drew up the red perogue into the middle of a small Island at the entrance of Maria’s river, and secured and made her fast to the trees to prevent the high floods from carrying her off put my brand on several trees standing near her, and covered her with brush to shelter her from the effects of the sun.”
Lewis and Clark hoped to be able to recover the stores and pirogue on the return trip. A few weeks later, in the midst of a grueling portage around the Great Falls of the Missouri River, they were forced to dig a second cache rather than transport more heavy equipment upriver. “Capt. C. also scelected the articles to be deposited in the cash consisting of my desk which I had left for that purpose and in which I had left some books, my specimens of plants minerals &c. collected from fort Mandan to that place,” Lewis wrote. “also 2 Kegs of Pork, ½ a Keg of flour 2 blunderbushes, ½ a keg of fixed ammunition and some other small articles belonging to the party which could be dispenced with.”
Also jettisoned at this point was the swivel gun that had been mounted on the expedition’s keelboat earlier in the expedition. Lewis wrote that they “deposited the swivel and carriage under the rocks a little above the camp near the river.” The white pirogue was dragged on shore and hidden in some willows below the Great Falls. On July 10, yet another deposit was made: the dismantled frame of Lewis’s ill-fated iron boat, which despite his tireless efforts could not be made watertight. “Had a cash dug and deposited the Fraim of the boat, some papers and a few other trivial articles of but little importance,” Lewis wrote with resignation.
The expedition’s third major cache was made about six weeks later, in mid-August 1805. After a long and anxiety-filled search, Lewis and Clark had finally found the Shoshone Indians and were negotiating for horses to carry them across the Rocky Mountains. Naturally, much of the remaining baggage had to be left behind. Near the Beaverhead River and the spot they called Camp Fortunate, they sunk their canoes in the river and buried everything they could not take across the Great Divide. On August 21, 1805, Sergeant John Ordway wrote: ” four men sent to dig a hole or carsh… this evening after dark we carried the baggage to the carsh or hole which we leave at this place. we took it to hide undiscovred from the natives. all the baggage which we carry with us packed up & pack Saddles made ready to cross the diveding ridge as soon as the horses return from the other Side.”
That was the final significant deposit, save for two canisters of lead powder that Clark buried on the Weippe Prairie once the Expedition had crossed the great divide and was camping near the Nez Perce. There was nothing to do now but hope for the best that the goods could be recovered for the return trip.
All in all, Lewis and Clark’s caches made out fairly well. On May 7, 1806, the Corps was headed for home and was back among the Nez Perce. Lewis wrote, “a man of this lodge produced us two canisters of powder which he informed us he had found by means of his dog where they had been buried in a bottom near the river some miles above, they were the same which we had buryed as we decended the river last fall.” The honest man returned the powder to the captains.
On July 8, 1806, the Corps returned to Camp Fortunate and the Beaverhead River. Desperate for a smoke, the men were particularly impatient to get into this cache. Clark wrote:
after dinner we proceeded on down the forke which is here but Small 9 Miles to our encampment of 17 Augt. at which place we Sunk our Canoes & buried Some articles, as before mentioned the most of the Party with me being Chewers of Tobacco become So impatient to be chewing it that they Scercely gave themselves time to take their Saddles off their horses before they were off to the deposit. I found every article Safe, except a little damp. I gave to each man who used tobacco about two feet off a part of a role took one third of the ballance myself and put up ⅔ in a box to Send down with the most of the articles which had been left at this place, by the Canoes this evening. I examined them and found then all Safe except one of the largest which had a large hole in one Side & Split in bow.
The opening of the oldest caches on either side of the Great Falls proved to be a bit of a disappointment. On July 13, the Corps of Discovery had reached their old camp at White Bear Island on the upper part of the portage route. Lewis had the upper portage cache opened and found that there had been some casualties. He wrote disconsolately:
found my bearskins entirly destroyed by the water, the river having risen so high that the water had penitrated. all my specimens of plants also lost. the Chart of the Missouri fortunately escaped. [This map was apparently lost at a later date.] opened my trunks and boxes and exposed the articles to dry. found my papers damp and several articles damp. the stoper had come out of a phial of laudinum and the contents had run into the drawer and distroyed a gret part of my medicine in sucuh manner that it was past recovery.
The next day’s dig yielded a little better news. Lewis wrote: “Had the carriage wheels dug up found them in good order. the iron frame of the boat had not suffered materially.” He dispatched Private Hugh McNeal to determine the state of the white pirogue and the cache at the lower portage camp. Fortunately, the white pirogue had survived the winter quite well. On July 27th, Sergeant John Ordway wrote, “we halled out the white perogue out of the bushes and repaired hir. about 12 we loaded and Set out with the white perogue and the 5 canoes.”
The red pirogue and the cache on the Marias were not so lucky. On July 28, Lewis was hugely relieved to rejoin with other members of the Corps of Discovery after his ill-fated exploration of the Marias River and hair-raising flight from his encounter with the Blackfeet Indians. Lewis wrote that upon reaching the mouth of the Marias “we heared the report of several rifles very distinctly on the river to our right, we quickly repared to this joyfull sound and on arriving at the bank of the river had the unspeakable satisfaction to see our canoes coming down.” After reconnoitering to make sure the party was safe and unobserved, Lewis had the last remaining cache at the lower portage camp opened.
“We found that the cash had caved in and most of the articles burried therin were injured,” he wrote. “I sustained the loss of two very large bear skins which I much regret; most of the fur and baggage belonging to the men were injured. the gunpowder corn flour poark and salt had sustained but little injury the parched meal was spoiled or nearly so. having no time to air these things which they much wanted we droped down to the point to take in the several articles which had been buried at that place in several small cashes; these we found in good order, and recovered every article except 3 traps belonging to Drewyer which could not be found.”
His disappointment at the loss of his bear skins was lessened by his strong desire to make tracks lest the Blackfeet catch up with them. Unfortunately, the red pirogue would not be making the trip. “Having now nothing to detain us we passed over immediately to the island in the entrance of Maria’s river to launch the red perogue, but found her so much decayed that it was imposible with the means we had to repare her and therefore mearly took the nails and other ironwork’s about her which might be of service to us and left her. we now reimbarked on board the white peroge and five small canoes and decended the river about 15 ms. and encamped on the S. W. side near a few cottonwood trees.” They had recovered as much buried treasure as they could, and it was time to move on.