In 1862 the first battalion of the regiment entered on active service in the Mississippi valley. It engaged in the Yazoo expedition under Sherman, who was by that time a major-general of volunteers, and took part later in Grant's operations around Vicksburg. The battalion won for its colors the proud inscription, "First Honor at Vicksburg," and lost 43.3 per cent of its force in the attack on the Confederates. Among the dead was its then commander, who died on the parapet. Sherman's nine-year-old son, Willie, who was with his father at Vicksburg, was playfully christened a "sergeant" of the Thirteenth battalion, and his death of fever in October, 1863, called forth a sorrowful letter from General Sherman to the commander of the Thirteenth. "Please convey to the battalion my heartfelt thanks," he wrote, "and assure each and all that if in after years they call on me or mine, and mention that they were of the Thirteenth regulars when Willie was a sergeant, they will have a key to the affections of my family that will open all it has; that we will share with them our last blanket, our last crust!" After the war the regiment was transferred to the West. It was employed in Kansas, Montana, Dakota, Utah, Wyoming and elsewhere until 1874, for a large part of the time serving almost continuously against hostile Indians. In 1874 it was moved to New Orleans, and was engaged on duty in the Department of the South for six years. During the labor riots of 1877 all but two companies were on duty at Pittsburg, Scranton, Wilkesbarre and other points in Pennsylvania. Then back to the West it went again, and, with some slight vacations, remained on the frontier until October, 1894, when it was transferred to various posts in New York State. CHAPTER XL. DIPLOMATIC RELATIONS TERMINATE. Grave Responsibilities Bravely Met--The Ultimatum to Spain--The Spanish Minister of Foreign Affairs Sends Minister Woodford His Transports--Our Consuls in Cuba Leave the Island--Fate of Americans Left Behind--Spanish Spies at Work--Playing a Desperate Game. None but those who were close to the men at the head of our Government just prior to the commencement of the war with Spain can realize with what solicitude they watched the development of the preliminary proceedings. With full appreciation of their grave responsibilities, knowing the power inherent in their positions to effect results, and yet cognizant as the days went by of their inability to prevent the fulfillment of fate, they endeavored to guide events so far as they could in a course which will hold them and the people blameless in the sight of the world for whatever might follow. That they withstood the strain so well bears testimony to their mental poise and strength of character.