Laxmi Bachanalaya
Legally available public-domain books and openly licensed reading materials.
Various
Sven Anders Hedin
Ernst Haeckel
Erich von Salzmann
Max Dauthendey
Jintaro Omura
Freiherr von und zu Richard Eisenstein
These books are free to read. Each is in the public domain in the United States; check your own country's rules before you copy or share one.