There came a shrill and a whistling sound,
Above, beneath, beside, and around,
Yet leaf ne’er moved on tree!
So that some people thought old Beelzebub must
Have been lock’d out of doors, and was blowing the dust
From the pipe of his street-door key.
This is from the poem called The Witches’ Frolic (1837). https://ebooks.adelaide.edu.au/i/ingoldsby/thomas/ingoldsby_legends/chapter9.html
What does 'pipe of his street-door key' here?