A few years ago, I was looking at our local church - which has a tall campanile style tower; and noticed the lightning rod on the highest point, and traced the copper strip down to earth. It made me wonder why other similarly tall buildings didn't have lightning rods - since it would seem that they would be equally vulnerable.
But then I took a walk around town, and discovered they they did!
All of the tall buildings I found have lightning rods and copper strips.
These had (presumably) always been there - presumably this is part of building regulations; but for decades I had never noticed them, except on churches.
Which all goes to show... something or another.
Note: Unlike what most people, including my younger self, think; lightning rods are not there either to attract lightning, nor to conduct a lightning strike safely into the ground. They are there to prevent lightning striking in the first place. This works because (in summary, as far as I remember) a tower sticking up from the surface of the earth gets polarized with an opposite electrical charge by the thunder clouds, and this opposite charge then streams up from the tower to make an "electrical path" up to the thunder clouds, down which path the lightning will strike. The purpose of the lightning rod is to conduct this charge from the point of the tower down into earth, before it gets a chance to accumulate and stream up to the clouds. Hope I've got that right.
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