Muller, Frederick. Papers, 1898 Jun. 30. 2 items. OS:M. Frederick H. Muller was captain of Troop E of the 1st United States Volunteer Cavalry (the "Rough Riders") during the Spanish-American War. Abstract of expenditures for the quarter ending June 30, 1898 shows the amount of ammunition used on May 28 and June 24 of that year. Quarterly return of ordnance and ordnance stores shows supplies received and used for the same dates. Both are signed by Captain Frederick Muller on June 30, 1898 at a military station in El Pozo, Cuba. Mss. 5248.