Interesting (defense) concept. Photography, not so much.
... A very British typology...
In a thousand years, if those things survive, extraterrestrial explorers will think them part and parcel of an ancient religious belief system...
The Mo'ai of their time. On our 1967 summer visit to Scotland and England I brought along a pair of baseball-sized rubber balls so my cousins & I could play catch (and, as it turned out, rounders). During a day-trip including a stop at such a sound mirror, my cousin John & I spent a good amount of time trying to work out how we could stand equidistant from it, throw a ball at the concave part and so play catch without the ball touching the ground. We never consistently succeeded. (There are photos of this too, but my cousin has 'em.)-Dave-