Seattle artist Gloria Bornstein based the piece on a Salish legend that whales once used an underground spring to pass between the two bodies of water. 
The inscription in English and Lushootseed is saying:
A Long Time Ago In The Land Of Chief Seattle, Whales Used To Pass From Elliot Bay To …
In the early 20th century, ethnographer John Peabody Harrington described a black hole on the beach of Seattle’s waterfront, “two blocks up from Pike Street,” called Sh tsh pau, meaning Stick into, blow. According to Duwamish folklore, young whales were said to travel through this hole from the bay to Lake Union. This location would be under Pier 57 at the foot of University Street, where its spring water once refreshed native clam diggers at the foot of Spring Street. Today, the pier’s historic carousel and Seattle’s Great Wheel repeat the circle motif. In local mythology, the actions of whales were believed to cause earthquakes.
