sentences:  In one story, the Laird of Lorntie went to aid a woman he thought was drowning in a lake near his house; a servant of his pulled him back, warning that it was a mermaid, and the mermaid screamed at them that she would have killed him if it were not for his servant.But mermaids could occasionally be more beneficent; e.g., teaching humans cures for certain diseases.Mermen have been described as wilder and uglier than mermaids, with little interest in humans.