Charles Varnum (1849 - 1936) was the Professor of Military Science (PMS) at the University of Wyoming from 1895 to 1898. He was the third PMS at UW. He is best remembered as one of three surviving officers from the command of Lieutenant Colonel George A. Custer that was defeated at the Battle of the Little Bighorn on June 26, 1876. He was awarded the Medal of Honor in 1890 for his action in another battle during the Indian Wars of the US.
Click this link to view a more thorough biography of Varnum at the National Park Service website.
Image: Public Domain. Unknown photograph, retrieved from National Park Service website 25 Jun 2015,(www.nps.gov/prsf/historyculture/images/varnum_1.jpg).