Magia Naturalis (in English, Natural Magic) is a work of popular science by Giambattista della Porta first published in Naples in 1558.
Its popularity ensured it was republished in five Latin editions within ten years, with translations into Italian (1560), French, (1565) Dutch (1566) and English (1658) printed.
Natural Magic was revised and considerably expanded throughout the author's lifetime; its twenty books (Naples 1589) include observations upon geology, optics, medicines, poisons, cooking, metallurgy, magnetism, cosmetics, perfumes, gunpowder, and invisible writing.
Its sources include the ancient learning of Pliny the Elder and Theophrastus as well as numerous scientific observations made by Della Porta.
Only two of Giambattista's teachers have been identified: Antonio Pisano, a royal physician in Naples, and Domenico Pizzimenti, a translator of Democritus.
It is believed that he was largely self-taught with an informal education that consisted of jovial discussions of scientific and pseudoscientific topics.
[1] The Acadéemies of Naples were shut down in 1547 due to 'political intrigue' and did not reopen until 1552, just six years before the original publication of Natural Magic.
He experimented with both convex and concave lenses in order to clarify the image of the lens and to provide a mathematical explanation for their refractive properties.
Giambattista was actually theorized to have priority in the invention of the telescope, but he reveals his secondary position to Galileo in an unpublished treatise that fails to discuss anything other than his contemporary's work.