On June 21, 1804, Jane Marcet published the second edition of Conversations on Chemistry, a book she had written to explain chemistry to women who were excluded from university lectures.

The book was widely read — including by Michael Faraday, who was a bookbinder's apprentice with no formal education and later credited Marcet's book with teaching him the chemistry that launched his career.

Marcet also wrote Conversations on Botany, which contained early clear explanations of what plants do with sunlight and air. The formal description of photosynthesis as a process was still decades away, but Marcet's accessible accounts of plant metabolism circulated widely in the early 19th century.

Because she was a woman, her books were initially published anonymously. The chemistry book was attributed for years to her husband, Alexander Marcet, a physician and chemist who helped her with the technical content.

The history of science is substantially a history of women who wrote clearly and accessibly about scientific concepts at a time when the scientific establishment required Latin, required university attendance, and required being a man — and whose work therefore circulated under other names or no names at all.

Marcet's identity as the author of Conversations on Chemistry was established in her lifetime. Her role in educating Faraday is frequently mentioned. Her own scientific thinking is rarely the subject.