Ernst Mach was born in Chirlitz, Moravia, in 1838 into a cultured, freethinking family. Practically for all of the scientist's long life, Austria-Hungary was ruled by Emperor Franz-Joseph, who reigned from 1848 to 1916. Mach's father, Johann, was an eccentric who had studied science and philosophy in Prague and who was, for a time, a private tutor to the sons of the Baron Brethon in Vienna. He preferred farming and his own schemes, including the surprisingly half-successful idea to raise silkworms in Austria.¹ Mach owed his first education in science to his father's garden-physics demonstrations.