Fort Union Trading Post Historic Structures Report (Part II) Historical Data Section

Edwin Denig described the palisades as "fronting [the river] 220 feet and running back 240 feet." Other dimensions vary from these but Denig's figures are considered to be the most accurate. He wrote also that the wall was 20 feet high. Other observers would have them lower: Catlin (1832) - 18 feet; Maximilian (1833) - 16-17 feet; Stevens (1853) - 16 feet. The pickets were hewn cottonwood and, according to Sprague (1843), one foot square. In contrast to the palisades of other fur posts, Fort Union's pickets were not buried in the ground; instead, they were founded upon a stone foundation. This method of construction did not enable the pickets to withstand the fierce winds of the Dakotas. In the fall of 1833 a strong wind knocked down two sides of the fort. To prevent this happening again, McKenzie had substantial reinforcements built inside. Denig described this new construction:

The pickets are fitted into an open framework in the inside, of sufficient strength to counter-balance their weight, and sustained by braces in the form of an X, which reaches from the pickets to the frame, so as to make the whole completely solid and secure, from either storm or attack.

This X-framing may be seen in the illustrations of Kurz (1852) and of the Soldier (1864). Denig also described how the top of this frame, about 15 feet above the ground and 8 feet wide, was boarded so as to make a gallery running around the palisades, "formed of sawed planks nailed to the cross beams from one brace to another. This balcony affords a pleasant walk all around the inside of the fort. . . . It is a favorite place from which to shoot Wolves after nightfall." Audubon asked Larpenteur to call him whenever he happened to see a wolf from this gallery. The walkway cannot be seen clearly, if at all, in the Kurz sketches (1851-52); but it definitely existed in 1864 when the Soldier's sketch showed a guard walking it. The troops laid new flooring that year according to Larpenteur's diary: "Soldiers making a walk on the gallery of the Fort to go from one Bastion to the other on their guards."

Several adventures befell the palisades over the years. In early 1832, a disastrous fire destroyed most of the west wall. McKenzie wrote that at least 170 new pickets had to be cut and shaped but that he had the damage to the wall repaired within five days. Besides the wind damage in 1833 (above), Kurz (1851-52) noted that the west wall blew down again "where the supports were badly decayed." In 1865, someone (Sioux were suspected) set fire to the outside of the walls. However, the fort's occupants quickly put out the blaze. These disasters required immediate repairs of course, but the pickets and their foundations also required constant maintenance over the years. Larpenteur's 1835 diary noted "Holmes painting the underpining of the sills around the outside of the Fort." Thirty years later, his diary stated that he "straightened a place in the east side of the Fort."

Generally, the various sketches agree on the appearance of the palisades. None show the chevaux-de-frise that Maximilian (1833) said existed. Nearly all of them show horizontal planks tying the pickets at both the top and the bottom of the walls. The most detailed drawings are the two Hays (1860). Here one sees that the western half of the south wall is divided into 8 panels. While these possibly were for added strength, the written documents do not mention them. A horizontal plank on the west wall most likely is emergency stabilization. A similar condition is found in the Corbett photograph (1866) of the north wall. The Hays sketches also show a series of dark markings on the west wall.

These are not otherwise identified but may be the ends of cross-beams used for reinforcement or something similar; detail of the same nature appears on the south wall of the unknown-artist sketch that shows the U. S. wagon. More puzzling is the meaning of the extreme western portion of the south wall, between the panels and the bastion in this drawing. No suggestions come to mind to help explain this.