Answer the following question given this paragraph: 

Although the idea that Earth is a magnet is centuries old, the discovery of why Earth is a magnet is a relatively new. In the early 1900s, scientists started using seismographic data to learn about Earth’s inner structure. A seismograph detects and measure earthquake waves. Evidence from earthquakes showed that Earth has a solid inner core and a liquid outer core (see the Figure below ). The outer core consists of molten metals, mainly iron and nickel. Scientists think that Earth’s magnetic field is generated by the movement of charged particles through these molten metals in the outer core. The particles move as Earth spins on its axis. The video at the URL below takes a closer look at how this occurs.


Q: What device detects and measuresee earthquake waves?


A:
seismograph