In this poem, the soul is personified as a woman (she) and Fright is a ghost or goblin.
To paraphrase:
She feels a ghost approach
And stop to look at her -
Salute her, with long fingers -
Caress her freezing hair -
(She feels a ghost approach and stop to look at her - salute her and,
with long fingers, caress her hair.)
If you want to change the aspect from simple to progressive, you get:
She feels a ghost approaching
And stopping to look at her -
Saluting her, with long fingers -
Caressing her freezing hair -
(She feels a ghost approaching and stopping to look at her - saluting
her and, with long fingers, caressing her hair.)
What is the difference in meaning? Not much. Though, as a matter of style, the verb form that follows feel (as a verb of perception) reflects duration. Compare the simple aspect/infinitive and the progressive aspect/present participle:
I felt the ground shaking for about half a minute.
I felt the
ground shake once.
Source: Grammaring — SEE, WATCH, HEAR,
LISTEN, FEEL, SMELL, NOTICE, OBSERVE + object + present
participle
Meanwhile, approach (draw near) already suggests duration, so the progressive is redundant, and stop — unless you’re pulling the train brakes — is a point in time . . .
I think Em knew what she was doing.