Just trawling re: Suo Gan because it was listed in the contents of "Songs of the Ages" which I listed on the schoolbooks thread yesterday. The words given by Snuffy above do not scan to the expected tune, and the version in the book mentioned is a different song under the same title (which matches Snuffy's scansion). So:

SUO GAN (An Ancient Welsh Lullaby)
From Parry's 'Welsh Harper' 1839

Hwi hwi, hwi hwi plentyn bach.
Hwi hwi, hwi hwi plentyn bach.
Hwi hwi, hwi hwi druan bach.
Hwi hwi, hwi hwi druan bach.

Short, to the point, and presumably repeat ad nauseum until child is asleep!

Only 8 bars (2*4 each repeated), so if anyone wishes to add ABC or MIDI please PM me & I'll e-mail a scan

CHEERS

Nigel