H. G. Wells 
The First Men in the Moon 
By The Author of The Time Machine

Cavor, a brilliant scientist who accidentally produces a gravity-defying substance, builds a spaceship and, along with the materialistic Bedford, travels to the moon. The coldly intellectual Cavor seeks knowledge, while Bedford seeks fortune. Instead of insight and gold they encounter the Selenites, a horrifying race of biologically engineered creatures who viciously, and successfully, defend their home.