The Battle of Warbonnet Creek was a skirmish characterized by a duel between legendary scout and showman "Buffalo Bill" Cody and a lone warrior he mistook for Cheyenne Chief Yellow Hand. The engagement is often referred to as the First Scalp for Custer because of this incident. It occurred July 17, 1876, in Sioux County in northwestern Nebraska.

After the defeat of George A. Custer at the Battle of Little Bighorn, many Native Americans joined with Sitting Bull and Crazy Horse, encouraged by the Indians' success. About 800 Cheyenne warriors set out from the Spotted Tail and Red Cloud agencies in Nebraska.

The United States Army was also receiving reinforcements. Colonel Wesley Merritt, commanding the U.S. 5th Cavalry Regiment, had set out to join with George Crook in Montana, guided by the legendary "Buffalo Bill" Cody. Merritt was able to intercept the Cheyenne warriors before he reached Crook.

Merritt planned an ambush. The veteran cavalry officer hid most of his 200 troopers inside covered wagons and posted sharpshooters nearby but out of sight. Spotting Merritt's seemingly unescorted wagon train along Warbonnet Creek, the Cheyenne warriors charged directly into the trap. A few warriors were wounded by the troopers, but the only real action of the engagement was a duel between "Buffalo Bill" and a young warrior named Hay-o-wei (translated as Yellow Hair). Cody pulled his Winchester carbine and killed the Indian, then pulled out a Bowie knife and scalped the dead man. The rest of the warriors under Chief Lone Wolf broke and fled so quickly that not a single trooper was killed or injured. Merritt was able to join with Crook, who in turn linked up with Alfred H. Terry, bringing a combined strength of the U.S. force to about 4,000.

A scout accompanying the cavalry misidentified the dead Indian as the important Cheyenne Chief Yellow Hand. Ever the showman, Buffalo Bill returned to the stage in October, his show highlighted by a melodramatic reenactment of his duel with the supposed Yellow Hand. He displayed the fallen warrior's scalp, feather war bonnet, knife, saddle and other personal effects.

Fort Reno was established as a permanent post in July 1875, near the Darlington Indian Agency on the old Cheyenne-Arapaho reservation in Indian Territory, in present-day central Oklahoma. Named for General Jesse L. Reno, who died at the Battle of South Mountain, it supported the U.S. Army following the Cheyenne uprising in 1874.

Following the Indian Wars the fort remained to protect the more peaceful Five Civilized Tribes from the Plains Indians farther west. Soldiers from Fort Reno also attempted to control Boomer and Sooner activity during the rush to open the Unassigned Lands for settlement. Among the units stationed here were the famed Ninth Cavalry of Buffalo Soldiers.

Hickok left his last mark on Hays during the summer of 1870. On the night of July 17, two drunken 7th Cavalry troopers, Jerry Lonergan and John Kile, apparently attacked him in a saloon. According to one account, Kile tried to get off a shot but the cap failed to explode. Before Lonergan could fire, or Kile pull the trigger again, Hickok got off two shots. One shattered Lonergan's knee, and the other wounded Kile, who died the next day.

In 1867, Harvard School of Dental Medicine was established in Boston, MA on this day. It was the first university-based dental school in America. The parent institution, Harvard College opened in Cambridge, Massachusetts, in 1636, with an enrollment of 12 students and one Master to teach all subjects. The School of Dental Medicine was established in close affiliation with the Harvard Medical School, another first which made the full scholarly and scientific resources of a university available to dental education.

In 1866, authorization was given this day to build a tunnel beneath the Chicago River. As Chicago grew, river traffic became increasingly heavy and slow so that the bridges over the river would be raised, open as much as a quarter of the time during the navigation season to accommodate large numbers of masted vessels, causing extensive traffic jams. Given the easy-to-excavate blue clay that underlies the city, Chicago planned the tunnel. Work began November 30, 1866 on this first US underwater highway tunnel. Completed January 1, 1869, the tunnel was 1605 feet long and cost over $512,000.