Complex sentence: She served as a mine depot in the Firth of Forth, and in 1906 her name was changed to "Actaeon II", and she became part of the Torpedo School at Sheerness.
Split into simpler sentences: She served as a mine depot in the Firth of Forth, and in 1906 her name was changed to "Actaeon II". She became part of the Torpedo School at Sheerness.