By the estuary where sea river clash br Froth surface broken but nothing torn, br Bubbles flattened like mushroom caps- br Frontier closes on sky below land, br Whence the diver's descent to underworld, br Without walls of life, beacon and back to coast br br Fellow rover. Travel worn, he spreads arms in vain br And vainly peers the whale's way and calls for pilot. br Beyond these limits as the mirage melts away, br Not the faintest ray enlightens the distant shore br Where the lost may steer or get the truth that lies br Along the unwalked way, beyond the last threshold.