The house is very solid - cinder block and brick, but then again we don't see many earthquakes here! The history of the brick is interesting, all taken from the Broad Street station after it burned down. Our little pocket neighborhood in Devon all used the brick from the wrecked part of the building.
Here's what the Broad street station used to look like:
http://en.wikipedia.org/wiki/Broad_Street_Station_(Philadelphia)