The book "Downing Street Mirrors: Some Political Reflections from the Man with the Cannon" was written by Harold Bagby - an English publicist and journalist of the first half of the 20th century. In his book, he collects his political reflections and memories of the time he worked in Downing Street, the central office of the British government. The author uses the metaphor of mirrors to reflect political processes and power structures, revealing important aspects of government work from the inside. This book is a valuable resource for understanding the political environment and intrigues of Great Britain in bygone eras.