"Historiae" survives in 123 codices, or bound manuscripts, all deriving from an original in the 9th century. As it was a partial text, already missing large pieces, they are partial as well. They vary in condition. Some are more partial than others, with lacunae that developed since the 9th century. The original contained ten "libri", "books," equivalent to our chapters. Book I and II are missing, along with any Introduction that might have been expected according to ancient custom. There are gaps in V, VI, and X. Many "loci", or "places," throughout are obscure, subject to interpretation or emendation in the name of restoration.