A mid-18th-century French treatise on dyeing wool and woolen fabrics by Hellot of the Académie Royale des Sciences, covering both the "grand et bon teint" (fast dyes) and the "petit teint" (fugitive dyes). It begins with vessels and instruments, then covers the woad (pastel) and indigo vats, blues, scarlets and crimsons from kermes, cochineal and lac, madder reds, yellows, fauve (browns) and blacks, and mixed colours. The second part covers petit teint dyes such as orchil, logwood, Brazil wood, fustic, annatto, Avignon berries and turmeric, and ends with an instruction on the "déboüilli" (boil-testing of dyed wool). It also includes the royal privilege and a note on preparing test felts. It is a technical, recipe-based text with no weaving drafts.