The well-known crack of a rifle, whose ball came skipping along the placid surface of the strait, and a shrill yell from the island, interrupted his speech, and announced that their passage was discovered.
An arc fault circuit interrupter (AFCI) is a circuit breaker that breaks the circuit when it detects an electric arc in the circuit it protects to prevent electrical fires. An AFCI selectively distinguishes between a harmless arc (incidental to normal operation of switches, plugs, and brushed motors), and a potentially dangerous arc (that can occur, for example, in a lamp cord which has a broken conductor).
Sparking and arcing are exactly what the AFCI breaker is looking for, and so it will interrupt the circuit power. The engineers who have designed these AFCI Breakers found that motors, like the ones found in the power drill, vacuums and treadmills produce a rhythmic, mechanical arc pattern.