William E. Lewis recorded around 150 pages of daily diary entries about his experiences in the United States Army's 7th Cavalry Regiment from March 2, 1903-September 8, 1903. He commented on aspects of life at Camp George H. Thomas in Chicamauga, Georgia, such as drill, an extended trip to an off-site firing range, and military personnel.
Lewis titled his diary "Happenings of the Seventh Regiment of Cav. stationed at Camp Geo. H. Thomas Chickamauga Park." Lewis regularly recorded discharges, illnesses, promotions, and transfers. He occasionally provided background information on soldiers such as "Private Beatty," a Civil War veteran (April 10, 1903); Juan Otero, a Cuban native who was born in Spain (April 15, 1903); "Quartermaster Sergeant Crombie," a member of the 7th Cavalry during the Battle of Little Bighorn (June 5, 1903); and Frederick Toy, a champion marksman and veteran of the Battle of Wounded Knee (June 9, 1903). The diary reports officers' suspicions about civilians selling moonshine to soldiers (June 16, 1903) and a band member's dishonorable discharge and sentence to hard labor for "instrumental insubordination" (July 9, 1903).
Other entries focus on daily camp activities, which included training exercises such as the "monkey drill" and firing practice. On one occasion, the regiment held an athletic competition (June 17, 1903), and Lewis often mentioned baseball games between teams of soldiers. From late July to late August, the 7th Cavalry Regiment marched to an off-site firing range. Entries from this period name the towns where the regiment camped and describe aspects of the march. Lewis shared a story about soldiers' attempt to capture a "wild dog" (August 16, 1903).
The book has 1 poem by Lewis, "The Regulars" (March 21, 1903), and his thoughts about the human desire to experience life from different perspectives (for example, as a member of a different race) (April 8, 1903). In his entry of June 25, 1903, he commemorated the anniversary of the Battle of Little Bighorn.