File contains materials regarding Dr. Schnackenberg’s service in the United States Navy including entrance picture negatives, a physical training manual of the United States Army from 1914, Navy registration forms and travel documents, a certificate of completion for Officer Indoctrination (1944), a humorous certificate of initiation into the "Solemn Mysteries of the Ancient Order of the Deep" (1944), and an affidavit acknowledging his call for active duty (1945), a letter of gratitude upon his release, a certificate of gratitude from Harry Truman (1945), forms related to his status as a member of the inactive reserve (1952-1953).