Which animal's name is slang for an informer who betrays his associates to the police?

In 1899, William Middlebrook patented a machine for making which office item, which can harm floppy disks if magnetized? The 1899 Battle of Magersfontein was part of which war? An 1899 film called "Frank Melville's Trick" what shows the title animal stepping over two ponies? Which secret society of Irish-American coal miners saw about 20 of its alleged members hanged in Pennsylvania in the la… In which 1900 Joseph Conrad novel does a young officer try to live down the cowardly act of abandoning a ship he though… British troops invaded the Orange Free State in 1900 during which conflict? Which 1900 children's book begins by saying that Dorothy "lived in the midst of the great Kansas prairies"? Which word names both a long coat worn by early motorists and a 1970s Plymouth car?