Answer:
White as the gleam of a receding sail,
White as a cloud that floats and fades in air,
White as the whitest lily on a stream,
Explanation:
Hyperbole is simply the use of exaggeration for literary effect.
This is a powerful tool that writers often employ to show the extent of something or the effect of that thing on another thing or person.
Therefore, the author compares his memories to the gleam of a receding sail, a cloud and the whitest lily on a stream.
