On Thu, 11 Dec 2008, Jules Richardson wrote:
  Maybe the sheer weight of the cabling needed for a
mainframe environment
 was just too much to justify running it overhead? 
    The SAGE installations used overhead wiring in cable trays.  They
didn't come much bigger than that.
Mike Loewen                             mloewen at cpumagic.scol.pa.us
Old Technology  
http://sturgeon.css.psu.edu/~mloewen/Oldtech/