"Imagine pressing a switch, and suddenly, you see a spark climbing upwards until it breaks at a certain point. This spark, called an electric arc, happens when we apply a whopping 25,000 volts across two points. The clever part? The arc chooses the narrowest gap where the air insulation is broken. As we keep the voltage on, the arc rises. Why? Because the air gets hot, and there's a magnetic effect at play. It's like a magical dance – the arc takes a longer and longer path until the voltage isn't strong enough, and the spark fades away. This magic trick is actually a safety feature in horn gap arresters. They create a temporary 'earth link' to shield electrical gear from sudden high voltages, keeping everything safe and sound."