"Steve" Gridley graduated in 1864 (moved up because of the war) in the bottom half of his class. Some of his classmates would go on to be well-known during the Spanish-American War like Robley Evans, who commanded the USS Iowa at the Battle of Santiago, and Charles Sigsbee, who was in command of the USS Maine at the time of her loss, and commanded the USS St. Paul during the war itself. (Both Evans and Sigsbee were at the Battle of Fort Fisher during the Civil War).
Gridley's first assignment was to the USS Oneida, which was part of Admiral David G. Farragut's blockading squadron. It was at the Battle of Mobile Bay where Acting Ensign Gridley got his baptism of fire. He would not experience another large action like this for thirty-four years, at the Battle of Manila Bay.
During the Battle of Mobile Bay, Gridley was [placed all the way forward on the USS Oneida, where he would watch the the channel for mines and give steering directions to Commander J.R.M. Mullany (the ship's commander). During the battle, the Oneida had eight men killed and thirty wounded (including Mullany).
Though a shell hit the Oneida close to where Gridley was stationed, he was unscathed. His commanding officer had this to write about his young ensign: "The conduct of Acting Ensign C.V. Gridley is beyond all praise. he had charge of the master's division and assisted in conning the ship from the topgallant forecastle."
When the war ended, Gridley was detailed to transport a group of Confederate prisoners to Texas who had accepted the option of going into exile in Mexico. On arriving, it was found the former Confederates would have no way of continuing south, as the bridges over the Rio Grande had been destroyed. In spite of them having been former enemies, Gridley did not abandon his passengers. He took it upon himself to transport them across to Mexico.
--Cooter