Pisa's Leaning Tower

The Tower in tiers of architraves,
Fair circle over cirque,
A trunk of rounded colon[n]ades,
The maker's master-work,
Impends with all its pillared tribes,
And, poising them, debates:
It thinks to plunge — but hesitates;
Shrinks back — yet fain would slide;
Withholds itself — itself would urge;
Hovering, shivering on the verge,
A would-be suicide!