Complex sentence: Caroline Furness Jayne (1873-1909) was an American ethnologist, and author of perhaps the first (and best-known) book of String figures, "String Figures and How to Make Them".
Split into simpler sentences: Caroline Furness Jayne (1873-1909) was an American ethnologist. She wrote perhaps the first, and best-known, book on string figures, "String Figures and How to Make Them".