Page "Agrippina the Younger" Paragraph 52

According to Suetonius, Nero was annoyed at his mother being too watchful and tried three times to poison Agrippina, but she took the antidotes in time and survived.

He then tried to crush her with a mechanical ceiling over her bed at her residence.

After this failed, he devised a collapsable boat, which would either have its cabin fall in or become shipwrecked.

Nero then ordered captains of a different boat to ram this boat while Agrippina was aboard.

Nero heard Agrippina survived the wreck so he ordered her to be executed and framed it as a suicide.