Within the temple, enclosed behind some chicken wire, are two light-blue flames coming out of the ground - fissures in the earth where sulphurous gas escapes to the surface.

When a pipeline wall breakdown occurs, fluid or gas escapes in the form of a high velocity jet.

For smaller attitude control thrusters, a compressed gas escapes the spacecraft through a propelling nozzle.

Eventually the gas escapes through a ceramic plug, and this permits mercury to fill the thimble.

The gas escapes into the atmosphere, the oxygenated water flows back through the downstream pipe.