Secrets of the Dead: The Nero Files Premiered Wednesday, February 20 on PBS (check local listings)
According to their descriptions, Nero has a trusted assistant prepare Agrippina's yacht with a trap door that will open and sweep her out to sea.
Cassius Dio writes the mechanism would then close and the boat would continue sailing, as though nothing had happened... Nero could easily have disguised a crime on the ship.
As Tacitus wrote, 'Nothing allowed of accidents so much as the sea.'
An experiment in a ship model basin will hopefully reveal the truth.
According to Tacitus, Agrippina's yacht was a 'trireme, a galley with three banks of oars on either side.
The mother of the emperor would have had a luxurious cabin at the stern of the ship.
Agrippina's yacht is reconstructed at a scale of 1 to 9 in the ship model basin.
The aim of the experiment is to determine what kind of modifications would have been necessary to create an opening in the ship that someone could fall through.
The experts are certain that trapdoors would have been the only possibility, and they install two flaps at the stern of the model.
One opens inward, while the other opens out into the water.
On dry land, both trapdoors work perfectly.
In the water though, things are very different.
Now it''s time to test the trapdoor theory.
The depth of the hull is reconstructed exactly.
The flaps are now underwater.
The door opening into the ship would have let water flow in immediately, stopping anyone from falling out and also quickly sinking the ship.
Given these results, the trapdoor must have opened outwards.
And yet, it can''t.
The water pressure keeps the flap closed, and the ship sails on as normal.
Perhaps more force is required.
Weights are placed on the trapdoor.
So much weight is needed to force the flap open, the ship begins to sink.
Approximately 2 tons would have been required to force the door open, but that would have sunk the ship before it ever left the harbor.
Additionally, once the door opened out, there wouldn''t have been a way to close it.
Water would have flooded in and sunk the ship.
The writers' descriptions just aren''t reliable as evidence.
'Telling the truth' didn't mean providing descriptions or reconstructions of events that were one hundred percent accurate.
Rather, the story had to be told well, and had to be built around a sweet center that increased the appetite and the attention of the readers.