A SIMPLE KEY FOR HENRY RIFLE WITH STAR GAZING AND ASTRONOMY FOR BEGINNERS UNVEILED

The e-book 'Guns, germs and steel' launched me to the fact that the Sahara desert truly isolated Sub-Saharan Africa from the developments elsewhere due to the fact the beginning of civilization until European colonialism. My major dilemma: Is that this true? Had been there significant isolated exchanges of information?: I also questioned over the b