Reading about "gamboge" I got to thinking about "gamgee" as in the name of the hobbit Sam Gamgee. In a note in the very last page of the Appendices to LOTR, Tolkien says of the name Gamgee that no reference to the name "Cotton" was intended. So I looked it up, and it turns out "Gamgee-tissue" is an absorbent cotton-wool for dressing wounds, and takes its name from one "S. Gamgee" (1828-86)!