Electricity, Lightning, and, in short, any current or electrical Atmospheric. impulse, like wireless telegraphic waves, is called _atmospheric_. Electricity, Electricity with a low potentiality and large current Voltaic. density. Electrification. The process of imparting a charge of electricity to any body. Electro-chemistry. The study of which treats of electric and chemical forces, such as electric plating, electric fusing, electrolysis, and the like. Electrode. The terminals of a battery, or of any circuit; as, for instance, an arc light. Electrolyte. Any material which is capable of being decomposed by an electric current. Electro-magnetism. Magnetism which is created by an electric current. Electrometer. An instrument for measuring static electricity, differing from a galvanometer, which measures a current in a wire that acts on the magnetic needle of the galvanometer. Electro-motive Voltage, which is the measure or unit of e. m. f. Force. (E. M. F.) Electroscope. A device for indicating not only the presence of electricity, but whether it is positive or negative. Electro-static Surfaces separated by a dielectric for opposite Accumulator. charging of the surface. Element. In electricity a form of matter, as, for instance, gold, or silver, that has no other matter or compound. Original elements cannot be separated, because they are not made up of two or more elements, like brass, for instance. Excessive Charge. A storage battery charged at too high a rate. Excessive Discharge. A storage battery discharged at too high a rate. Excessive Overcharge. Charging for too long a time. Exciter. A generator, either a dynamo or a battery, for exciting the field of a dynamo. Exhaustive Discharge. An excessive over-discharge of an accumulator. F. The sign used to indicate the heat term Fahrenheit. Fall of Voltage. The difference between the initial and the final voltage in a current. Field. The space or region near a magnet or charged wire. Also the electro-magnets in a dynamo or motor. Flow. The volume of a current going through a conductor. Force, Electro-magnetic. The pull developed by an electro-magnet. Frictional A current produced by rubbing dissimilar Electricity. substances together. Full Load. The greatest load a battery, accumulator or dynamo will sustain. Galvanic. Pertaining to the electro-chemical relations of metals toward each other.