Hughes photographed various guns during the war. This one is a 75 mm American gun also referred to as a field gun. Hughes and fellow soldiers who were part of the 35th Division had been trained to use these. The men pictured with the gun are unidentified. James C. Hughes, as part of the 35th Division, left Fort Sill, Oklahoma, and traveled to Hoboken, New Jersey, where he boarded the troop ship "Ceramic" on May 18, 1918. Hughes arrived in Liverpool, England, on June 1, 1918 and then landed at Le Havre, France, on June 9, 1918. Hughes fought in the battles of St. Michael and the Meuse-Argonne. He was at Verdun on Armistice Day, November 11, 1918. He took no photos of the actual fighting. He did take many photographs after the war as part of the Army of Occupation until he left France on July 18, 1919. A full biography of James Clark Hughes is available at the link below to Kansapedia.