"Traité élémentaire de chimie, tomes 1 & 2" by Antoine Laurent Lavoisier is a textbook published in 1789. Considered the first modern chemistry textbook, it redefines what an element is and catalogs thirty-three substances—though only twenty-three qualify by today's standards. Lavoisier presents groundbreaking ideas about chemical reactions, introduces the first chemical equation, and articulates a principle that would become known as the law of conservation of mass, fundamentally transforming how scientists understand matter.
Wikipedia page about this book: en.wikipedia.org/wiki/Trait%C3%A9_%C3%89l%C3%A9mentaire_de_Chimie Wikipedia page about this book: fr.wikipedia.org/wiki/Trait%C3%A9_%C3%A9l%C3%A9mentaire_de_chimie