Groves was actually AZ #158 James Grove, in for Attempted Rape, Attempted Murder & Murder
Spinks was AZ #360 Donald Spinks, in for Murder in the District of Columbia
"Salthorse" is unidentified.

Jimmy Groves was quite a piece of work.

According to Warden James A Johnston, Groves was born in 1900. "When he was only 15 years old when he was arrested in 1915, in St. Joseph, Missouri, and handed over to the Juvenile Court. In 1919, he was arrested in Stockton, California, for carrying concealed weapons. In 1920 he was committed to the Utah State Penitentiary for burglary, but escaped in 1921. In 1923, he was sentenced to the Washington State Penitentiary for burglary, was paroled in 1923, and then violated his parole.

"The next entry on his record states that he joined the Army, and within 13 days after enlistment, was charged with attempt to rape the daughter of an Army Officer at Fort Leavenworth, was found guilty by a Courts Martial, and was sentenced to a 20-year term on July 8, 1924. On August 30, 1928, he was sentenced to an additional consecutive sentence of 20 years for attempt to murder another inmate.

"Grove had built up such a record of assaults on other inmates at Leavenworth, that he was classified as a dangerous menace and transferred with the first group sent to Alcatraz. In 1935, he was returned to Leavenworth for additional mental examination, after which he was sent to the Federal Medical Center at Springfield, Missouri. From Springfield he was sent back to Leavenworth, and in July, 1939, he was again transferred to Alcatraz, where he continued his assaultative behavior. This culminated in the killing of a fellow inmate, for which he was convicted of second degree murder, given another sentence of 15 years on January 13, 1947, and since then he has been kept in "D" Block."

James A. Johnston
-Alcatraz Island Prison: And The Men Who Live There