The cultural clock runs mainly upon ruined fragments of matter. No matter to what hazardous lengths we let out our line they still withdraw again, and further, into the depths. ... however, runs mainly upon ruined fragments of matter recovered from refuse heaps and graveyards, from abandoned cities and buried villages. Only the arts of material nature have survived; of music and dance, of talk and ritual, of all the arts of temporal expression practically nothing is known elsewhere than in the Mediterranean world, save through traditional survivals among remote groups.