and coolness at Hatcher's Run, on the 26th of October, established his reputation at once in the Second Corps. At last, in the latter part of November, a long-desired leave of absence was obtained, and the memory of all sufferings drowned in the delights of home. After a stay of thirty days he returned; but in the latter part of January, 1865, was sent home again under a severe attack of illness. Those last days at home were among the brightest of his life. A brevet as Major for gallantry in action reached him then, when such rewards are sweetest. On the 23d of March he set out for the army. At Fortress Monroe he proposed to remain a day with a friend, ‘but soon after breakfast, hearing that there was fighting at the front, rushed down to the wharf, and luckily found a steamer just starting with despatches, and came up on her.’ The last campaign of the Army of the Potomac had begun. Wounded at Antietam, Major Mills had passed safely through the battles of the Wilderness, two at Spottsylvania, North Anna, Shady Grove, Bethesda Church; June 17th, at Petersburg,—the mine, the siege, the Weldon Railroad; Preble's Farm and Hatcher's Run, October 26, 1864; besides skirmishes. On the 31st of March, 1865, at Hatcher's Run, Virginia, on the same spot where he had been exposed to the fire of a Rebel battery the year before, he fell. Major-General Humphreys, on whose staff he was, thus describes his death:—
I rode a short distance to a small hollow, from which I could, unseen, as I believed, observe the operations that were going on under my direction; but in a few seconds I was conscious that some one by my side had fallen. Turning towards him, I received the last look of recognition from your son. So fatal was the shot, he could have felt no pain.A solid shot had struck his side, and he must have dropped dead from his horse. The funeral took place at the College Chapel in Cambridge. His body lies in the cemetery at Forest Hill.