magnetite

[Eng. magnet; suff. -ite ( Min.).] Min.: An ore of iron sometimes found well crystallized in forms belonging to the isometric system, the octahedron being the most frequent, though the rhombic dodecahedron also is found uncombined with others. Dodecahedral faces striated parallel to the longer diagonal; octahedrons fre magnificence Magneto-electric machine: A machine in which an electric current is generated by the revolution of one or more soft iron cores surrounded by coils of wire, about the poles of a magnet or magnets; or an armature (keeper) may rotate before the poles of stationary coils. Used medically in uterine hæmorrhage, asphyxia, . In many cases it can be employed by the patient without the aid of a doctor. [FARADIZATION.] magneto-electricity, subst. The science which treats of the production of electricity by means of who succeeded in generating an electric spark by magnet. It was discovered in 1831 by Faraday, suddenly separating a coiled keeper from a per manent magnet. He subsequently discovered that an electric current existed in a copper disc rotated between the poles and a magnet. This is not to be confounded with electro-magnetism, discovered by Ersted, which investigates the action of an electric current on a magnet, the proce being the converse one to that in the former case. măg-nět-o-graph, s . [Eng. magnet, and Gr. graphō to write, to draw.] An instrument which registers automatically the condition and changes of terrestrial magnetism.