'the unfathomed distances in himself'

From the first, the baby stirred in the young father a deep, strong emotion he dared scarcely acknowledge, it was so strong and came out of the dark of him. When he heard the child cry, a terror possessed him, because of the answering echo from the unfathomed distances in himself. Must he know in himself such distances, perilous and imminent?

—D.H. Lawrence, The Rainbow (1915)