Sarawak Chamber was so big, Mad Phil explained, that it almost certainly contained new passages—particularly in the roof, where no one had ever searched. Although it's tempting to think of caves as similar to mine shafts—tunnels that slope relatively straightforwardly down—natural caves are nonlinear and ex-pand and contract according to the movement of rocks, the meandering of water, the work of chaos.
His nickname apparently had come from a canoeing stunt during his university years, but Mad Phil was known for climbing cave walls that no one else would even attempt. He and Eavis planned to ascend into the roof of Sarawak Chamber, searching for tunnels that ran through it like hidden passages in the ceiling of a mansion.