It’s now official: the earth is a musical instrument! Seismic vibrations produced by earthquakes and volcanoes are music to the ear.

Professor Frank Scherbaum of the University of Potsdam’s department of geophysics has produced a CD of recordings made by the earth’s volcanos and earthquakes. And now a couple of teachers in Northern Ireland have used it to explore scientific themes.

Anne-Marie McLaughlin from St Catherine’s Primary School in Armagh gave her nine to ten-year-olds no hint of the music’s origin. She simply darkened the room, got them into a meditative mood and then played an illustrative section.

“The responses were amazing and imaginative,” says Anne Marie McLaughlin, “they ranged from the music of dark caves to bath water and scary horror music. Some drew monsters, others water themes, graveyards and zombies.”

The children were astounded when she told them the music came from the earth itself. This led to discussions on science, earthquakes, volcanoes, geology, maps, geography, rhythm, beat and a host of other areas. “We used wooden and plastic bricks to represent the floors of houses and buildings.

We used two neighbouring tables to represent a fault line. We talked about San Francisco and Los Angeles being on the San Andreas fault and so on.

“We built tower blocks and by vibrating tables, first on their own and then two tables together, we saw how our buildings stood up to our earthquakes.

We marked out three possible sites for buildings to test, one far from the fault-line, one in the middle of the table and one site right by the fault-line. We tested each one, and most of the time the building located at the edge of the fault-line was the first to go.”

As well as earth science, the CD offered a chance to explain that music is, in fact, also science, or physics. Our reaction to “music” as distinct from mere sound or “noise” is a very clearly defined phenomenon. When we pluck a guitar string, say, we may hear the note D. But in effect this will be made up of a fundamental frequency, plus a number of supporting eigen frequencies.

But the children still found it difficult to accept that no musical instruments had been used in the recording. In fact, German composer Wolfgang Loos had “arranged” the material of Professor Scherbaum to form a symphony (www.traumton.deshopindex.htm - look for “kookon” and then inner earth), but no other sounds had been introduced.

Using home tape-recorders to capture sounds brought pupils on to concepts like frequency, amplitude and amplification. Linux software enables the class to record these sounds and display the spectrographs visually, showing the “quality” of the sounds.

For Bernie Cargill who teaches a class of mixed adults at Omagh FE college in County Tyrone, percussion serves other functions. Her part-time students range in age from 18 to 21, all with either moderate physical or communication difficulties, all on STEP (Special Training Education Program). Verbalisation is a challenge for most of them. Bernie Cargill beat out a rhythm and got the class to reciprocate. They talked about other kinds of beat, like heartbeats and those caused by thunder, wind and waves, or banging doors. Talk of nature leads to the idea that the earth itself might have a beat. Perhaps the earth itself might be thought of as a person. This personification raised the question of how we might get close to the earth - to communicate with it. Some suggested the night sky, rural walks, the beach, lying on grass. Many suggested listening. At that point she introduced the Scherbaum CD.

She prepared for it by getting the class to beat rhythms by hand on their desk tops. But when she put on the music, 21-year old Tracey, who has mobility problems, was reduced to tears. She found the sounds quite frightening. Down’s syndrome Steven, in his mid-20s, soon had his arms moving to the music. “They couldn’t fathom how the music was made. They couldn’t think of instruments that would make that kind of music,” says Bernie Cargill.

She then got them to think about “sounds they could feel but not hear.”

Soon this progressed to the rumbles that the earth might make. “They were impressed once they discovered that it was in fact the earth’s rumbles they’d been listening to. They had made a connection, they’d not made before.”

Software is DAP a digital audio processor for Unix, see www.cee.hw.ac.ukrichardk See also Book of Linux Music amp; Sound by Dave Phillips, No Starch Press, pound;37.49 paperback