The yellow fog that rubs its back upon the window-panes
The yellow smoke that rubs its muzzle on the window-panes
Licked its tongue into the corners of the evening
Lingered upon the pools that stand in drains,
Let fall upon its back the soot that falls from chimneys,
Slipped by the terrace, made a sudden leap,
And seeing that it was a soft October night
Curled once about the house, and fell asleep.
If we are talking about the poem above. I am pretty sure the answer is personification.