Electric Currents, vi, 67-85; alternating and direct, 152-3 (see Alternating, Direct Currents); attracting and repulsion of, 20-1; cause of, iv, 265, 271, 273, vi, 46, 72; detection, 91; direction, 54-7, 59, 124; distribution (see Power Transmission); effects on human body, vii, 246-9; electron theory, vi, 123, 152, vii, 366; flow, vi, 46, 47, 67-9; follow least resistance, 96; Galvanic Faradic, and Franklinic, vii, 242, 243, 245; heat and light production by, iv, 310-12, vii, 337-8; induced, iv, 303-8, vi, 22 (see Induced Voltages); intensity, vii, 370; leakage, 371; magnetic effects of, iv, 273-9, 286-7, vi, 20-1, 88-91; measured by ammeters (see Ammeters); overloading lines, vi, 9, 72; production, 46, 72 (see also Dynamos, Electric Batteries, Thermal Couples); protection against overloading, vii, 34-50; selenium control valve, v, 332; surges, vii, 16-18; units and measurements, iv, 277-85, vi, 69-76, 82, 84-5; values, effective and maximum, 346-7; value in oscillating circuits, vii, 289-90; velocity, Watson's study, xvi, 123; wire capacity table, vii, 58 Electric Discharges, iv, 264-5, 267, 269, vii, 366; atmospheric, i, 157, 158-62; fog dispersal by, 94; in vacuums, iv, 317-18; nitrogen fixation by, viii, 73, 74, 346; rain-making by, i, 340; through gases, vii, 216, 301-2 Electric Eel, vi, 16, 64, xii, 160-1 Electric Energy, vii, 368; conversion into heat, 89, 303-5; due to difference of potential, iv, 263, 264, 265; equivalents, vii, 382; transmission (see Power Transmission); unit of, vi, 82; unit (joule), iv, 284, 294, 310, 312, vii, 370 Electric Fans, vii, 76-7, ix, 317 Electric Fishes, catfishes, xii, 161; electric eel, 160-1; torpedo fish, 149-50 Electric Furnace, iv, 312, vii, 302-12; history and uses, xvi, 189-91; invented by Acheson, vii, 301; operation and products, viii, 283-4 Electric Hammer, vi, 94