Electric torch. Simulated X-ray of an electric torch. It contains three batteries (across centre) for supplying electrical power to the bulb. This bulb (centre left) is at the centre of a reflector, a bowl-shaped (parabolic) mirror that reflects light from the bulb and throws it forward, focusing it as a narrow beam of light for better visibility. The switch to turn the torch on and off is between the bulb and the battery compartment.