thumb|right|Frontispiece of an English translation of Natural Magick published in London in 1658.
' (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.
Natural Magic is an example of pre-Baconian science. Its sources include the ancient learning of Pliny the Elder and Theophrastus as well as numerous scientific observations made by Della Porta.
Author
Giambattista della Porta (also known as John Baptist Porta) was born in Vico Equense, Italy, between October 3rd and November 15th, 1535 and was the second of three sons. The Porta family belonged to the ancient nobility of Solerno, granting them a modest fortune until Giambattista's father, Nardo Antonio della Porta entered the service of Emperor Charles V in 1541. This allowed the family to alternate residences between Vico Equense and Naples. The nature of Giambattista's formal education is unknown. 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. Giambattista began collecting 'secrets of nature' when he was just fifteen. These secrets were eventually compiled and made into the twenty books of Natural Magic.
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. Della Porta had many friends in Naples’ most prestigious academies, and he even opened one himself sometime before 1580: Accademia dei Segreti. Academics gathered in della Porta's home and discussed the 'secrets of nature'. Later in life, della Porta became associated with Rome's Accademia dei Lincei. He had a close relationship with its founder, Frederico Cesi and even wrote a compend of his family history. Porta's reputation soared in the academy and he was second only to Cesi, until the enrollment of Galileo to the academy in 1611. In the same year, della Porta was entered into Oziosi in Naples, the city's most renowned literary academy. Della Porta intended to compile the secrets of nature. However, Giambattista was skeptical of the discoveries of the past and insisted on making his own through experimentation. Again in his preface he says, "In our method I shall observe what our ancestors have said; then I shall show by my own experience, whether they be true or false…."