who traded by caravan required a light and portable medium of 
payment. This need was less for those who, like the 
Phoenicians, traded by sea. Portability, as a means of 
expediting and extending the effective distance of action, was 
also notably illustrated by papyrus. The alphabet was one thing 
when applied to clay or stone, and quite another when set 
down on light papyrus. The resulting leap in speed and space 
created the Roman Empire.

     In the industrial age the increasingly exact measurement 
of work revealed time-saving as a major aspect of labor-saving. 
The media of money and writing and clock began to converge 
into an organic whole again that has brought us as close to 
the total involvement of man in his work, as of native in a 
primitive society, or of artist in his studio.