"The word's exactness
slips from children's tongues."
The word is "border." Clarke hints at how horrified she is to see children being indoctrinated. They learn the word pedagogically, without knowing the hateful implications of the idea.
"His eyes are glass, each hair a needle of light.
He's pegged by his claws to the floor like a shirt on the line.
He is a soul. He is what death is. He is transparency,
a loosening floe on the sea."
In this excerpt, Clarke tries to capture the wonder of childhood imagination in describing her teddy bear from long ago. She captures the plastic, plush essence of the bear in its eyes, hair, and stuffing. To a child, however, the manufactured exterior must necessarily contain magic. The child sees the enormity of imagination in this bear.
"Before you, found in an old book
marking a page, a longhand manuscript."
This is a "crash blossom" sentence, meaning the author intentionally misleads the reader in the first half of the sentence. It represents a chasm of ideas, playing on the reader's subconscious associations. The manuscript is the subject of the sentence, as it lies tucked away in a book waiting to be discovered. The ambiguity of interpretation in this sentence is intentional and unexpected, forcing the reader to actively engage with the meaning of the words.
"the band still plays
to the drum of the waves,
to the drum of the waves."
Romanticizing the wreck of the Titanic, Clarke imagines the ghosts of the band continuing the play. Music which outlasts death is a common way of communicating longing, as if those musicians never found peace. Instead of playing music, now they listen to the rhythm and tone of the waves.