Usor:Jondel/agenda/Crystal

Historic Roots of Crystallography The earliest descriptions of external forms of crystals were made by the Roman scholar Pliny the Elder (24 AD-79 AD), who was killed observing an eruption of Mt. Vesuvius. In his Historia naturalis. Pliny mentions a six-sided quartz crystal: Quam sexangulis nascatur lateribus non facile ratio inveneri potest, eo magis quad neque mucronis eadem species est. Throughout antiquity, astrological-alchemical speculations regarding crystal structures were rife. No crystallomorphological discoveries were made during the Middle Ages because of the era's preoccupation with jewels and their supposed healing and magical powers. After Pliny, over one and a half millennia passed before the Belgian Ariselmus Boetius de Boodt (1550-1632) engaged in the study of the geometric forms of crystals. De Boodt, who was Emperor Rudolph II's personal physician at the Royal Court in Prague, curated the emperor's gem and mineral collection. In his work Gemmarum et lapidum historia libri V (1609), de Boodt refers explicitly to "Lapides, qui hebent figuram certam mathematicum";

At the beginning of the 17th century, the first optical instruments, the telescope and the microscope, came into use almost simultaneously. The pioneering work Micrographia (1665) by Robert Hooke (1635-1703), the inventor of the compound microscope, contains numerous illustrations and descriptions of crystals that he observed under the microscope [ILLUSTRATION FOR FIGURE 3 OMITTED]. Many sketches of crystal forms are contained in the famous letters that the Dutch microscopist Antony van Leeuwenhoek (1632-1723) wrote to the Royal Society of London between 1678 and 1685. This tradition was later continued by the Englishman Henry Baker (1698-1774) in his essay Employment of the Microscope (1753), with dozens of detailed descriptions and drawings of crystalline substances. All these works paved the way for exact and reproducible mathematical observations based on scientific crystallography.