Book excerpt: A sequence of 12 pages was torn at an early date from the one medieval manuscript (known as M) on which our knowledge of Aeschylus’s Choephori (Libation Bearers) depends. This sequence contained the end of the previous play Agamemnon, which is preserved in three later manuscripts, and the beginning of the Prologue of Choephori. The current study seeks to determine as accurately as possible the number of missing lines, taking into account the length of the pages in a particular quire of M and the space that would have been occupied by the last part of Agamemnon and by any material occurring between the texts of the two plays. From all this it is calculated that the number of lines of Choephori missing from M was probably in the range 36 to 53 and very probably in the range 32 to 55. Even the lowest of these figures is higher than previous estimates. The study concludes by considering what the missing portion could have contained. Some fragments are quoted by other authors and these may have been clustered at the beginning of the Prologue, but it is possible to imagine plenty of material that could have occupied the gap between the last of these fragments and the first surviving line in M.