Potomac Town in February

THE BRIDGE says: Come across, try me; see how good I am.
The big rock in the river says: Look at me; learn how to stand up.
The white water says: I go on; around, under, over, I go on.
A kneeling, scraggly pine says: I am here yet; they nearly got me last year.
A sliver of moon slides by on a high wind calling: I know why; I’ll see you to-morrow; I’ll tell you everything to-morrow.