SEE FOR YOURSELF
The molten rock called magma
moves through the Earth's crust
under pressure. You can
produce a similar effect if you
roll up a nearly-finished tube
of toothpaste. The pressure
squeezes the paste towards
the cap. Make a small hole
near the cap ond keep
squeezing, toothpaste will
ooze out of the hole like lava
from a volcano.