Eye of rabbit, harp string hum, turn this water into rum!

The spell that Seamus Finnigan uses to try and turn his goblet of water into rum. Much like everything else that he tries to put spells on, the water explodes in his face.

Seamus: Eye of rabbit, harp string hum, turn this water into rum!
Harry: Ron, what's Seamus trying to do to that glass of water?
Ron: Turn it to rum. Actually managed a weak tea yesterday, before--
BOOM