Having proceeded from 'f' Eridani to 'e', now place this star at your lower left corner of your binocular field of vision. You'll find the much brighter theta Eridani on the upper right corner.

Theta Eridani now carries the name Acamar, a variation on Achernar (End of the River) since it was once the terminus.
  Theta is a pleasant binary of two bright stars (3.3, 4.4) with a positioin angle of 88º and separation of 8.2", visible in medium-sized telescopes.

Now place theta on the upper left of your field of vision. You'll see two stars to the west, one over the other: binoculars. These are iota and 's Eridani'.

From iota the river descends straight south to 's' then further south (about seven degrees) to kappa. I see it as a multiple falls, bouncing from 's' to kappa and continuing further down ...

We've nearly made it the full length of the river.