his view from the popular one. His view was based on what may be the first in-depth lithic analysis of the objects in his collection, which led him to believe that they are artifacts and to suggest that the historical evolution of these artefacts followed a scheme. Mercati examining the surfaces of the ceraunia noted that the stones were of flint and that they had been chipped all over by another stone to achieve by percussion their current forms. The protrusion at the bottom he identified as the attachment point of a haft. Concluding that these objects were not ceraunia he compared collections to determine exactly what they were. Vatican collections included artifacts from the New World of exactly the shapes of the supposed ceraunia. The reports of the explorers had identified them to be implements and weapons or parts of them. Mercati posed the question to himself, why would anyone prefer to manufacture artefacts of stone rather than of metal, a superior material? His answer was that metallurgy was unknown at that time. He cited Biblical passages to prove that in Biblical times stone was the first material used. He also revived the 3-age system of Lucretius, which described a succession of periods based on the use of stone (and wood), bronze and iron respectively. Due to lateness of publication, Mercati's ideas were already being developed independently; however, his writing served as a further stimulus. The usages of Mahudel and de Jussieu On 12 November 1734, Nicholas Mahudel, physician, antiquarian and numismatist, read a paper at a public sitting of the Académie Royale des Inscriptions et Belles-Lettres in which he defined three "usages" of stone, bronze and iron in a chronological sequence. He had presented the paper several times that year but it was rejected until the November revision was finally accepted and published by the academy in 1740. It was entitled Les Monumens les plus anciens de l'industrie des hommes, et des Arts reconnus dans les Pierres de Foudres. It expanded the concepts of Antoine de Jussieu, who had gotten a paper accepted in 1723 entitled De l'Origine et des usages de la Pierre de Foudre. In Mahudel, there is not just one usage for stone, but two more, one each for bronze and iron. He begins his treatise with descriptions and classifications of the Pierres de Tonnerre et de Foudre, the ceraunia of contemporaneous European interest. After