The Lemon Fool

Facinating story about part of Britian's coastal defences against enemy aircraft prior to the invention of radar.

https://www.bbc.com/news/in-pictures-46348917

I found some of the structures quite beautiful. I'm pretty sure that 99% of people who come across them have no idea what they are. I know I wouldn't have had a clue.

Interesting little snippet - thanks for posting. Speculating over such things - when one hasn't a clue - can be entertaining, and now with online resources like google and wikipedia one can often very easily resolve bafflement or satisfyingly confirm a guess.

Seeing structures like that used for military purposes of course has lots of history. Archimedes at Syracuse was the first to spring to mind (mirrored the sun to set fire to the enemy fleet), but if we allow the use of decoys, distractions and deceptions I think it goes back even further.

In another fascinating story, a great natural sound mirror is the seat of a democracy established there in 930 A.D. (having previously been organised on a more ad-hoc basis). The Þingvǫllr became a regular venue because a citizen could speak at the rock face and be heard by a big crowd, so the venue enabled a parliament open to every citizen to participate.