=5.= To wait the far-off Heraclean thaw,
Heraclean—Hercules. What chained Titan did Hercules release?
=12.= His purpose called him at the Big Horn’s mouth—
Locate the Big Horn. What purpose? Who was there?
=18.= And took the bare, foot-sounding solitude
Why “foot-sounding”?
=22.= He seemed indeed a fugitive from Death etc.
Another reference to Hugh’s fancy that he had actually died.
It gives added force to that fancy to make his frosted breath
suggest a shroud.
=24.= Now the moon was young
Note the phase of the moon for later reference.