In 1872, General John Gibbon, U. S. A., with a considerable party, made a tour of the Park, passing by the usual route from Mammoth Hot Springs _via_ Mt. Washburn, the Grand Cañon, and the Lake, to the Firehole Geyser Basins. On his way home he attempted to ascend the north Fork of the Madison, following an old trail; but he abandoned the attempt after going a few miles. His name, which was given to the river, has also attached to many other features along that valley. In 1873, Captain William A. Jones, of the Corps of Engineers, passed through the Park as part of a more extended reconnaissance. He was the first to carry a party through the "impassable barrier" of the Absaroka Range. Jones Creek, just east of the northern portion of the Yellowstone Lake, shows where the party entered the Park. From the Lake the expedition passed down the east bank of the river to the valley of Junction Butte; thence west to Mammoth Hot Springs; thence back over the usual trail _via_ Tower Creek, Mt. Washburn, the Grand Cañon and Mud Geyser, to the Lower Geyser Basin; thence _via_ the Upper Basin to the west shore of the Yellowstone Lake; thence to the Upper Yellowstone River; thence through Two-Ocean Pass and Two-Gwo-Tee Pass to the valley of Wind River. The chief results of this expedition, in the line of original discovery, were the passage of the Absaroka Range, the verification of the traditional "Two-Ocean Water," between Atlantic and Pacific Creeks, in Two-Ocean Pass, and the discovery of the extremely easy pass (Two-Gwo-Tee[AI]) over the Continental Divide, between the Snake and Wind Rivers. Prof. Theodore B. Comstock accompanied the expedition as geologist. A valuable report of the reconnaissance appeared in 1875.[AJ] [AI] So named by Captain Jones for one of his Indian guides. [AJ] See Appendix E. In 1875, Captain William Ludlow, of the Corps of Engineers, made a reconnaissance from Carroll, Montana, on the Missouri River, to the Yellowstone Park and return. In the Park he followed the previously traveled routes and developed little in the line of original discovery. He succeeded, however, in obtaining a very accurate measurement of the height of the Yellowstone Falls, and his report[AK] forms one of the ablest brief descriptions of the Park extant. Among his civil assistants was George Bird Grinnell, now widely known as the editor of _Forest and Stream_, and as one of the most steadfast and watchful guardians the Park has ever had. [AK] See Appendix E. During the same season a distinguished party, consisting of the Secretary of War, Gen. W. W. Belknap, and several prominent officers and civilians, with Lieutenant G. C. Doane, of National Park fame, as guide, made a complete tour of the Park. An exceedingly interesting narrative[AL] of the trip was written by Gen. W. E. Strong, who was a member of the party. [AL] See Appendix E.