For me, the poem is effective despite itself. The image is strong & the poem communicates primal emotion. But i stumble on some of the rhymes & word choices (some seem rhyme forced). The poem's dark effectiveness for me makes me hope it's not some kind of subtle parody.
S1L5 - rhymes on on - Read aloud, this is no problem. On the page, among end stopped strong rhymes it forces too much emphasis on the word on.
S2L5 - and through a human brain - brain is misused - hate etc. can run through a mind, not through a brain. Rhyme forced.
S5L5 - And thinks: when I am dung, - rhyme forced
The poem might do better without S5. The point that despair, hate, etc. ring down the ages has already been made. It would be better, I think, to end with the effect on the scholar.
I think I will probably remember the image of the scholar and the bone.
Cross posted with Julie.