Researchers cast dead bodies
Under all the ash and pumice that Mount Vesuvius' eruption left behind, many bodies were found. Italian architect Giuseppe Fiorelli discovered many of these had left holes in the ash layers after collapsing in 1863. He came up with the concept of injecting plaster into these holes to produce plaster casts of the Pompeii mummies. Since then, as they work to learn more about what transpired during this enormous tragedy, researchers and other architects have found this to be helpful.