merely the abrasive traction principle—runners, skids, and skis 
preceded wheels for vehicles, just as the abrasive, semirotary 
motion of the hand-operated spindle and drill preceded the full, 
free rotary motion of the potter’s wheel. There is a moment of 
translation or “abstraction” needed to separate the 
reciprocating movement of hand from the free movement of 
wheel. “Doubtless the notion of the wheel came originally from 
observing that rolling a log was easier than shoving it,” writes 
Lewis Mumford in Technics and Civilization . Some might object 
that log-rolling is closer to the spindle operation of the hands 
than to the rotary movement of feet, and need never have got 
translated into the technology of wheel. Under stress, it is more 
natural to fragment our own bodily form, and to let part of it 
go into another material, than it is to transfer any of the 
motions of external objects into another material. To extend 
our bodily postures and motions into new materials, by way of