The Black Cabinet by Patricia Wentworth

Patricia Wentworth (1878-1961) was a master of the traditional English mystery novel. Dora Amy Elles was born in India, and following the loss of her first husband, she began writing, publishing her first novel in 1910. Miss Maud Silver, the former governess whose heavy figure, liking for Tennyson, and enthusiasm for knitting served to mask a bright brain, was introduced in the 1920s and became her most famous character. Miss Silver is the definitive representation of the English style of cozy mysteries, alongside Agatha Christie's Miss Marple.