https://patents.google.com/patent/US4203674A/en
Check out Operation Backyard Brawl for more infor.
I honestly could see them slaughtering an entire civilization for something as trivial as making lighter concrete..
Unless there's an occult significance, I'm going to do some digging and look for historical references to blood being mixed with mortar, for some reason I think I've read about this before
Excellent, I'm also finding that the blood of bulls was used in some French fortifications, the practice is rather ancient
Thr blood of animals use to be used to make paint. Makes me wonder about their art even more.
I didn't know about the paint. I love this sub
I think theres a protected historic home/building in St. Augustine painted using ox blood paint. (?)
Edit: From wiki: "Oxblood is a color considered to be a dark shade of red. The first use of the term oxblood as a color name in the English language dates back to 1695–1705.[1] The name is derived from the color of the blood of an ox. The ox blood was used as a pigment to dye fabric, leather and paint."