[…] like a sexton delving into a grave, possibly in quest of a jewel that had been buried on the dead man’s bosom, but likely to find nothing save mortality and corruption.

One person says that there is more to it: The guyascutus Ieadeth the wangdoodle wheresoever he willeth.

The poem re-enchants the bull by setting imaginary walls and thresholds around it.

He laughed again, plummily. Sounds as though he'd committed the murder himself.