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what a cool read, thanks a bunch! Best part "more remarkable was the process to strengthen the block’s composition. Not only were the blocks kept out in the cold and rain, but it’s also rumoured that they were peed on by the engineers. As strange as it may seem, urine has a nitriding effect as it contains compounds which form hard crystals on the surface of metal. Sword makers in the Middle Ages discovered that steel blades quenched in urine were harder than those that weren’t."
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