According to Wikipedia: "L. T. Meade was the pseudonym of Elizabeth Thomasina Meade Smith (1854-1914), a prolific writer of girls' stories. She was born in Bandon, County Cork, Ireland.
She began writing at 17 and produced over 300 books in her lifetime. Her most famous book was A World of Girls, published in 1886. She was also the editor of a popular girls' magazine, Atlanta. She also co-authored a number of notable mystery novels. With Robert Eustace, she wrote The Brotherhood of the Seven Kings, which featured a gang headed by a female criminal mastermind, Madame Koluchy. Also with Eustace, she wrote The Sorceress of the Strand, which had another female criminal, Madame Sara. With Clifford Halifax, M.D., she wrote Stories from the Diary of a Doctor."
