I forgot to grab a picture of the TB in Hinckley, MN, but I do have a picture with a script referencing the Great Hinckley Fires of 1894. The cache visited is located at a memorial for the lives lost during that fire.
Thomas H "Boston" Corbett was a Union army soldier during the United States Civil War. However, he's more well-known as the man who killed John Wilkes Booth. Booth had assassinated President Abraham Lincoln during a performance of Our American Cousin at Ford's Theatre in Washington, DC on April 14, 1865.
Corbett had disappeared near Hinckley, MN in 1888, and is presumed to have died during the Hinckley Fires that took place on September 1st, 1894.