> It must have been terrifying to be in a pillbox if the enemy managed to get close enough to throw grenades in or, even worse, if they had a flamethrower.
Terrifying yes, but what this article doesn't mention is that you generally have a hole for kicking grenades into. You do this when you dig foxholes as well.
From memory, it wasn't so much that they were fake ventilation ducts, but that they were plumbed in a manner that dropping a grenade in them at the upper level caused them drop out at your feet. Kind of like how flushing your toilet doesn't cause water to flow up from your shower drain.
Still pretty terrifying and you're not going to hear the second one falling in after your eardrums are gone from the first bang in such an enclosed space :(
Terrifying yes, but what this article doesn't mention is that you generally have a hole for kicking grenades into. You do this when you dig foxholes as well.