What does geophone mean? (Split into “geo” and “phone”) A geophone is a
type of disc shaped as microphones connected to earpieces.

What things were they listening for on the Geophones?
They try to recognise the sounds of the bombs or stuff.

What other things could they probably hear?
(if not sure, read through this for a hint).  They could hear enemies,
and some other stuff. 

Explain in your own words how a Geophone works (add a picture of one). 
A typical geophone consists of a mass suspended by means of mechanical
springs.

Describe a day in the life of a Geophone operator during WW1 in Arras,
from the time he got up to the time he went to sleep again. By moving one disc in an
arc round the other until a particular sound was heard with exactly equal intensity in each ear, the
direction of the sound was located in the line at right angles to that between the centres of the two discs,
a compass bearing of which could be taken.

The tunnellers kept constant track of an enemy. A geophone is a ground
motion transducer that has been used by geophysicists and seismologists
to convert ground movement into voltage. Through the geophone, it was
sometimes possible for a miner to hear the enemy packing their explosives.
When that noise stopped, it meant the inevitable explosion could happen at
any time.Geophones were helpful, but they also caused stress. Using one
meant sitting in a dark tunnel for hours, straining to hear the faint tap of the
enemy’s picks – and being able to distinguish this sound from many others.