“Respecting the universality of terrestrial magnetism, a modern author observes: ‘It is a curious sight,’ says Professor Faraday, ‘to see a piece of wood, or an apple, or a bottle of water repelled by a magnet; or, taking the leaf of a tree, and hanging it up between the poles, to see it take an equatorial position.’ We have learnt that magnetism is not limited to ferruginous [iron-containing] matter; we know that the ancient doctrine of the universality of the property is true.”