At 6 A.M. President and party leave on special train to visit headquarters of Army of Potomac and battlefields in vicinity of Antietam, Md. Party consists of Gen. McClernand, Capt. Wright Rives of McClernand's staff, Marshal Lamon, Ozias M. Hatch, Illinois politician, John W. Garrett, president of B. & O. Railroad, and others. Arrives Harper's Ferry at noon. Maj. Lawrence Kip and Capt. Samuel S. Sumner escort President to Gen. Sumner's headquarters. In afternoon Gen. McClellan arrives from camp and with President reviews troops at Bolivar Heights. Lincoln spends night in Harper's Ferry. Lamon, Recollections, 147-48; LL, No. 1277; Official Records—Armies 1, XIX, pt. 1, 10; Evening Star (Washington, DC), 3 October 1862, 2d ed., 1:6.

Sends letter of congratulation to King William I of Prussia on birth of grandson. Abraham Lincoln to William I, 1 October 1862, CW, 5:448-49.