[D] An interesting reference to the name "Yellowstone," in an entirely different quarter, occurs on Pike's map of the "Internal Provinces of Spain," published in 1810. It is a corrupt Spanish translation in the form of "_Rio de Piedro Amaretto del Missouri_," (intended of course to be _Rio de la Piedra Amarilla del Missouri_) river of the Yellow Stone of the Missouri. No clue has been discovered of the source from which Pike received this name; but the fact of its existence need occasion no surprise. The Spanish had long traded as far north as the Shoshone country, and had mingled with the French traders along the lower Missouri. Lewis and Clark found articles of their manufacture among the Shoshones in 1805. There is also limited evidence of early intercourse between them and the Crow nation. That the name of so important a stream as the Yellowstone should have become known to these traders is therefore not at all remarkable. There is, however, no reason to suppose that the Spanish translation antedates the French. It certainly plays no part in the descent of the name from the original to the English form, and it is of interest in this connection mainly as showing that, even at this early day, the name had found its way to the provinces of the south. We thus find that the name, which has now become so celebrated, descends to us, through two translations, from those native races whose immemorial dwelling-place had been along the stream which it describes. What it was that led them to use the name is easily discoverable. The Yellowstone River is pre-eminently a river with banks of yellow rock. Along its lower course "the flood plain is bordered by high bluffs of yellow sandstone." Near the mouth of the Bighorn River stands the noted landmark, Pompey's Pillar, "a high isolated rock" of the same material. Still further up, beyond the mouth of Clark's fork, is an extensive ridge of yellow rock, the "sheer, vertical sides" of which, according to one writer, "gleam in the sunlight like massive gold." All along the lower river, in fact, from its mouth to the Great Bend at Livingston, this characteristic is more or less strikingly present. Whether it forms a sufficiently prominent feature of the landscape to justify christening the river from it, may appear to be open to doubt. At any rate the various descriptions of this valley by early explorers rarely refer to the same locality as being conspicuous from the presence of yellow rock. Some mention it in one place, some in another. Nowhere does it seem to have been so striking as to attract the attention of all observers. For this reason we shall go further in search of the true origin of the name, to a locality about which there can be no doubt, no difference of opinion.