Breathing Tube Used When Viewing Coral Reefs
Puzzle 16 of Auction House Hard Pack
Question is: Breathing Tube Used When Viewing Coral Reefs
and the answer is: SNORKEL
Word Meaning:
SNORKEL — (underwater diving) A hollow tube, held in the mouth, or mounted on and opening into a diving mask, used by swimmers for breathing underwater.
Definitions from Wiktionary.