What is the significant of the Rain in the story and it's impact on the major character?

The rain falls nearly ceaselessly throughout the entire narrative. Within moments of going ashore to Pago Pago, the characters are driven inside by the rain. The rain pounds down throughout most of the scenes in the narrative and stops, finally, only when Davidson has killed himself. Dr. Macphail seems particularly troubled by the persistent rain and comments "'If it would only stop raining for a single day it wouldn't be so bad"' (p. 42), indicating how wearing the continual downpour becomes. The rain is symbolic of the power of nature and also of the ceaseless turmoil of Davidson.