In 1555 Dei Secreti del Reverendo Don Alessio Piemontese was published in Bologna. In 1558 an English translation of that Italian book of secrets was published (and is now available online in digitized form). This book was wildly popular, translated into several language in the first few years of existence and then published in more than a hundred editions until the late 18th-century. It is now generally accepted that the author is not Alexis of Piedmont but an alchemist named Girolamo Ruscellai.
I’ve studied two books of secrets over the past 10 years; the Secreti of Isabella Cortese and the Secreti of Alessio Piemontese. I was fortunate enough to be able to examine a copy of the 1561 edition of Isabella’s secrets at the Bibloteca Nazionale in Venice. The books of secrets contained recipes for many uses – medicinal, cosmetics, hygiene, and dyeing as well as for making household items like soap and ink. These books are important because they contain information on the scientific knowledge of the time as well as practical information on daily life in Renaissance Italy.
One of my favorite recipes from the Alessio Secreti is for Imperial Oil:
“To make oile Imperial, to perfume the haire or beard of a man, to rub his handes or gloves with, and to put also into the lye or water, wherein princes or great mens clothes be washed: and this oyle may a man make with cost enough, & also with little charge and expence [sic]”Alessio Piemontese/ Girolamo Ruscellai 1558
My redaction contained the following: myrrh oil, rose essential oil, rose-hip seed oil, dried cloves, crushed cinnamon, styrax, musk tincture, civet tincture, ambergris tincture, grape-seed oil. I combined these in a glass container, sealed it, set it in the sun for 8 days then strained it for use.
De’ secreti del reuerendo donno Alessio Piemontese, prima parte, diuisa in sei libri, In Venetia: per Sigismondo Bordogna, 1555.
Eamon, W. Science and the Secrets of Nature: Books of Secrets in Medieval and Early Modern Culture (Princeton: Princeton University Press, 1994).
“The Secrets of Alexis. A Sixteenth Century Collection of Medical and Technical Receipts.” https://journals.sagepub.com/doi/pdf/10.1177/003591573002400256