Making Leather

Page 3 of 5

Brain Tanned Elk Hide

close-up of a brain-tanned elk hide

Photo ©2012 by Kris Townsend, use with permission.

This elk hide is folded such that you can see moving left-to-right: scrape marks, an eyelet used to tie and stretch the hide to a frame, and the hide's smooth side.

On January 23 Lewis reported: "The men of the garison are still busily employed in dessing Elk's skins for cloathing." Regrettably, he was compelled to add that "they find great difficulty for the want of branes [brains]     we have not soap to supply the deficiency, nor can we procure ashes to make the lye; none of the pines which we use for fuel affords any ashes; extrawdinary as it may seem, the greene wood is consoomed without leaving the residium of a particle of ashes.–"

There are a number of different ways of tanning or preparing hides for use in making clothing. The one that traditionally had been used by a majority of North American Indians for countless generations was the one the Corps' leaders had in mind, judging from Captain Lewis's plaint. It involved "bucking" and "wet scraping," followed by "brain tanning." The first step in tanning the integument, or hide of a large quadruped such as a deer or an elk, was—and still is—to soak it in a caustic solution of lye (potassium hydroxide), which would normally be concocted of water and wood-ash. That process is called "bucking"—hence "bucked skin" or "buckskin."1 It sterilizes the hide, preventing bacteria from producing an obnoxious odor. Next, three layers of the hide had to be scraped off while they were still wet. They were, 1) the outermost layer, called the epidermis; 2) the papillary or "grain layer," which holds the hairs' follicles; and 3) the very thin inner membrane that separates the fibrous layer from the animal's flesh. After the scraping was finished, the remaining fibrous layer had to be rinsed to remove all traces of the caustic bucking. It was a painfully taxing, tedious process.

Then that clean layer had to be soaked for several hours in a thick, soupy mixture of the animal's brain tissues in water, then wrung out and stretched by hand to allow the naturally emulsified brain oils to separate and soften the fibers, thus assuring permanent pliability of the leather. Braining might have to be repeated two or more times in order to make certain that every part of the fiber network has received all the brain solution it can hold. The historic recipe was based on the premise that a deer or an elk has enough brains to tan its own hide, so the men's frustration over insufficient brains can only be explained by the necessity to butcher their kills so far from the Fort that if extracted from the skull and carried back along with the meat, brain tissues, which are more susceptible to decay than meat, would be useless on arrival. But if they were left in the skull, the weight of the head would be more than the hunters could handle, given the urgency of getting the best meat to the smokehouse. Soap mixed with an emulsified oil could have been used in place of brains, but as Lewis said, their soap supply was exhausted. Brain tanned leather is not waterproof, but if the fibers of the leather were not thoroughly treated with brain oil, and were subjected to an intensive soaking such as Clark experienced on his six-day hunting trip in mid-February, especially that night when circumstances compelled him to stay out all night in a violent rainstorm clad only in his leather shirt and overalls (see his journal entry for 11 February 1806), the insufficiently oiled fibers would assume the stiff texture of rawhide when they dried out.

None of the journalists revealed whether they ever found a firewood that would leave ashes that could be used to make lye. Douglas-fir would have served their needs better than most other available species in terms of heat, smoke, and ash residue. It is possible, even likely, that their good friend Coboway, a headman of the Clatsops, or someone from his village, provided them with either material assistance or helpful advice, for he and many of his tribesmen would have learned their own foolproof way of tanning their families' clothing.

It is conceivable that the Americans could have made pearl ash soap by mixing lye with potassium bitartrate (see "Cream of Tartar" in the "Interactive Index" to the list of medicines Lewis ordered in Philadelphia.) But they only had two pounds of it, which wouldn't have made enough to cure all the hides they needed. In their medicine kit they carried some Castile soap, but the exact amount is unknown. In Philadelphia Lewis bought 17½ pounds of it from Israel Whelen on May 28, 1803, but the ultimate "Recapitulation of Purchases by the Purveyor for Capt. Lewis" lists only 12 pounds. Since the price, $1.68, was the same in both lists, one of the poundage figures must have been incorrect. Castile soap was an expensive "vegetable" soap imported from the vicinity of Castile, Spain, that had become popular for its supposed medicinal values. It would have been unthinkable to waste it on curing leather.2 (On March 7, Lewis relieved Private Bratton's severe back pain with a liniment he concocted of wine, camphor, castile soap and laudanum.) Castile was a "vegetable" soap made of lye (sodium hydroxide), which most likely would have been imported from the vicinity of Castile, Spain.3 At any rate, by March 13, Sgt. Gass was able to report, as they began packing to leave Fort Clatsop, that they had managed to make 338 pairs of "mockasons" for their homeward journey. "This stock," he pointed out, "was not provided without great labour," as most of them are made of the skins of elk. Each man has also a sufficient quantity of patch-leather," presumably to trim to size and place or stitch inside a moccasin as it began to wear thin in spots. What undoubtedly made the cutting and sewing of the leather "great labor" is that elk skin is thicker and stronger than deer hide. For that reason it is also less prone to stretching—which is the main reason it was used to braid ropes for lining their boats and canoes after the fiber ropes wore out.

  • 1. The definition of the compound noun "buckskin" in the OED (Oxford English Dictionary) erroneously states that buckskin is "leather made from the skin of a buck," obviously on the false supposition that the initial component of the compound noun refers to "the male of several animals." Here the OED errs by exclusion: a male deer, antelope, or rabbit is called a buck, whereas a male elk or bison is called a bull, although the hide of either of the latter two can also be made into "buckskin." In fact, the "buck" in buckskin properly refers to the object defined in both elements of the third of the OED's eleven different meanings of the nominative case of that noun. A "buck" in that sense is defined as a solution of "[l]ye in which linen, yarn, or cloth"—or the skin of a large quadruped, either male or female—"is steeped or boiled as a first step in the process of buck-washing." An explanation of the processes of buck-washing and brain-tanning will be found in Matt Richards, "Traditional Tanners," at (accessed February 22, 2014), in "Tan Your Own"/"Wet Scrape vs. Dry Scrape."
  • 2. Pursuant to Army regulations requiring soldiers to keep themselves clean, they had begun their journey with what was no doubt expected to be a sufficient supply of soap to last the entire trip: "50 lb of soap" (see "Outfitting the Corps," Fig. 2), plus 12 pounds of Castile soap (Jackson, Letters, 1:95). We don't know when they ran out of it, or perhaps lost part of their supply when a canoe was overturned or one of the pirogues was swamped. However, Lewis's initial purchases of supplies in Philadelphia were based on the original plan for an expedition of 15 men, and if they neglected to buy more soap in Saint Louis before they headed up the Missouri River, their 15-man supply would have been severely attenuated, so that having enough surplus to use in hide tanning would have been unlikely.
  • 3. The recipe for Castile soap, which uses olive oil rather than animal fat as its base, enhanced with palliative laurel-berry oil (from the bay tree, Laurus nobilis), originated in the city of Aleppo, Syria, on the eastern Mediterranean coast. It was carried to Spain and Italy during the 12th century by immigrant Muslim soap makers. But the laurel tree is not native to continental Europe, so in order to succeed in the competitive marketplace, soap manufacturers in the region of Castile-La Mancha concentrated on improving the quality of their olive oil soap. Widely known for its mild, curative effect, Castile soap came to be used by American physicians and "first responders" to cleanse flesh wounds.