Col. Milton Cogswell, the Deputy Governor of the Soldiers' Home at Washington, died sud- denly of apoplexy in that institution yesterday morning. Col. Cogswell was born in Indiana about the year 1828. He entered the United States Mili- tary Academy at West Point in 1845 and was grad- uated in 1849, when he was appointed brevet Sec- ond Lieutenant in the Fourth United States In- fantry. He was promoted to be a Second Lieuten- ant the same year, and served in garrison at Sack- ett's Harbor, N.Y. In 1850 he was assigned to duty on the frontier, was afterward recalled and detailed as Assistant Professor of Mathematics at West Point, where he remained until 1856, having in the meantime been made a First Lieutenant. When the war broke about, Col. Cogswell went into active service with his regiment, and in May, 1861, was promoted to the rank of Captain. In July, 1861, he was made Colonel of the Forty-Second New-York Volunteers, and at the battle of Ball's Bluff was captured by the Confederates and incar- cerated in Libby Prison, until exchanged. For gal- lant and meritorious services at the time of his cap- ture, he was brevetted Major. He resigned his Volunteer commission in 1863, and was placed in command of his former regiment, the Eighth In- fantry. In the last Richmond campaign, Col. Cogswell served as Paymaster-General of the Ninth Army Corps, and was brevetted Lieuten= ant Colonel on July 30, 1864, for gallant and meritorious services before Petersburg. He was made a Major in 1864, and was brevetted Colonel in 1865 for gallant and meritorious services during the rebellion. At the close of the war he was as- signed to garrison duty at Baltimore, and after- ward served as Acting Judge-Advocate of the De- partment of North Carolina. He also served as As- sistant Commissioner of Musters and Assistant Commissioner of the Freedmen's Bureau in the same State. In 1868 he was made Provisional Mayor of Charleston from March to July, and was placed in charge of civil affairs at Summerville, S. C., the same year. He was afterward performed va- rious duties in the South and on the Western fron- tier until 1871, when he retired from active service on account of disability contracted in the line of duty.