The seismic wave kept going for four years, but the worst was over after about six months.
Seismic waves travel at a particular speed in the Earth.
It would, they said, create a seismic wave of similar programs across the country, shifting students, money and attention from public to private schools.
However, if the seismic waves were reflected back at him, he would be injured.
And the tiny earthquakes usually began soon after a particularly large seismic wave passed through the region.
First measurements are made of seismic waves passing through a material.
It is seismic waves that we feel as shaking during an earthquake.
For an instant he thought that another seismic wave was passing beneath them.
It is these seismic waves that cause the ground to shake near an earthquake.
Seismic waves move more quickly through rock than through air.