Oldenburg, [484].
Old World, fire-drill, fire altar, sacred fire, oil press, millstone, axial rotation, etc., [494-504];
civilizations compared with New World, [504-609], [525];
summary and conclusions, [544].
Oliva, Padre Anello, [132], [150], [154], [156], [157], [164].
Ollin, in Calendar-stone, [12], [13], [14], [15], [54]
(see also [Nahuiollin]).