It’s the willed trick of concentration
  that makes of these heat-heavy
bogged declivities —the graves of
  boulders we’ve levered up
to line the footpath to the house —
and of the sweat, sluicing down
  into the wristbands
of our canvas gloves, run-off
  from the glacial peaks
that once surrounded
  the bowl of the prairie.
It’s the pioneer trick cowboys
  use, and construction
workers and roadcrews, and old
  as weather, though it’s given
hip status now, and called
  “Visualizing” or“image
therapy,” a kind of negative capability:
  the mirage is really a glimpse
of the real world, but telescoped
  so it seems we never arrive
there Mirage pulled the wagon-
  trains toward the horizon
and tugged babies from the darkness.