Periodic table
The organization of the periodic table can be used to derive relationships between the various element properties, and also to predict chemical properties and behaviours of undiscovered or newly synthesized elements. Russian chemist Dmitri Mendeleev published the first recognizable periodic table in 1869, developed mainly to illustrate periodic trends of the then-known elements. He also predicted some properties of unidentified elements that were expected to fill gaps within the table. Most of his forecasts proved to be correct. Mendeleev's idea has been slowly expanded and refined with the discovery or synthesis of further new elements and the development of new theoretical models to explain chemical behaviour. The modern periodic table now provides a useful framework for analyzing chemical reactions, and continues to be widely used in chemistry, nuclear physics and other sciences.
Iguvine Tablets
The Iguvine Tablets, also known as the Eugubian Tablets or Eugubine Tables, are a series of seven bronze tablets from ancient Iguvium (modern Gubbio), Italy. The earliest tablets, written in the native Umbrian alphabet, were probably produced in the 3rd century BC, and the latest, written in the Latin alphabet, from the 1st century BC. The tablets contain religious inscriptions that memorialize the acts and rites of the Atiedian Brethren, a group of 12 priests of Jupiter with important municipal functions at Iguvium. The religious structure present in the tablets resembles that of the early stage of Roman religion, reflecting the Roman archaic triad and the group of gods more strictly related to Jupiter. Discovered in a farmer's field in the year 1444, they are currently housed in the Civic Museum of the Palazzo dei Consoli in Gubbio.