Any imaginative person feels this sense ever deepening upon him on looking long at the prairies.
11. Save for a welter of cawing crows,
What is the effect of the cawing of the crows in the general stillness?
Note that the meter is intentionally changed. What effect?
13. One faint star, set above the fading blush, etc.
What is the effect of the mention of the star and its growing from faint to clear?
16. For answer, the horse neighed.
What is the effect of the neighing of the horse?
17. Some vague mistrust now made him half afraid, etc.
Mistrust of what? Is disaster near?