Complex sentence: The mermaid legend has been extended beyond the creation of the Doom Bar--in 1939, Samuel Williamson declared that there are mermaids comparable to Sirens in the area, who lie in the shallow waters and draw ships in to be wrecked.
Split into simpler sentences: The mermaid legend has been extended beyond the creation of the Doom Bar. In 1939 Samuel Williamson declared there are mermaids comparable to Sirens in the area, who lie in the shallow waters and draw in ships to be wrecked.