The first steamboat to ascend the Yellowstone as far as Pompeys Pillar was the Josephine, commanded by the famous Missouri River captain, Grant Marsh (1834–1916), with a team of railroad right-of-way surveyors and a military escort. That was in June of 1875. Captain Marsh celebrated his achievement by scribing his ships name in the sandstone, and by "nailing Old Glory to a stout staff on top of the Pillar, where he left it an emblem of Columbia's supremacy over the lonely land." Joe Bailey, a member of the military escort, engraved his own tag on the far side of the rock from Clark's.
On April 17, 1876, the 7th U.S. Infantry, marching down the Yellowstone, bivouacked a few hundred yards downstream from Pompeys Pillar. On the 18th, 32-year-old Lt. James H. Bradley wrote in his journal:
Our boys have been busy all day transmitting their names to posterity by carving them in the soft sandstone of Pompey's Pillar. Captain Clark, . . . on the occasion of his descent of the Yellowstone in 1806, discovered the rock and gave it its name. "Wm. Clark, July 26, 1806" is the inscription he left behind, and it still appears as distinctly as when graven there seventy years ago.
But a cavalry vandal today disfigured the inscription by carving his own wretched name over the letter "K", for which he deserves to be pilloried. When taken to task about it he is said to have defended himself by saying: "Be Jases, it's a dom lie anyhow, for there wuz niver a white man in this country sivinty years ago."
He remarked on the S.S. Josephine's name on the rock, and then, somewhat sympathetically, mentioned the disappointment many of the other officers felt at the sight of this famous landmark, for they had expected to find a slender shaft standing needle-like above its surroundings. "The name is something of a misnomer," he pointed out.
Lt. Bradley missed the fateful battle on the Little Bighorn just four months later, but was killed in the Battle of the Big Hole with the non-treaty Nez Perce bands in August of 1877. Evidently he was a serious student of the Lewis and Clark expedition; his duffel contained three copies of the captains' journals and two of Patrick Gass's.