The words at the end of "South" are spoken by Holly Hunter in the film "The Piano" by Jane Campion:

"At night! I think of my piano in its ocean grave, and sometimes of myself floating above it. Down there everything is so still and silent that it lulls me to sleep.
...
There is a silence where hath been no sound /
There is a silence where no sound may be /
In the cold grave, under the deep deep sea."

Again, the last three verses are taken from the poem "Silence" by Thomas Hood (1799-1845).