The geological framework
The same thing [an eruption between Thera and Therasia]
happened again in our own time during the second con-
sulship of Valerius Asiaticus. Why do I mention these
curiosities? So it may be clear that fire is not extinguished
even by a sea covering it and that its force is not prevented
from bursting out even by an enormous mass of water.
Asclepiodotus, the pupil of Posidonius, says that the
height of water through which the fire reached before it
had broken through was two hundred feet.
Seneca, Naturales Questiones, 2.26.6
Seneca lived in the first century of the Christian era. He
was the palace philosopher of the emperor Nero in Rome.