They were a backward people without any writing.

As what is commonly called the Riemann sphere (after Bernhard Riemann, 1826–1866), the parabolic sphere ̇S² ̇provides a conformal model for the complex projective line C ℙ¹.

Is it at all probable, that there will ever be a civil war in America, about the presidentship of the United States?

Solar panels allow for energy transfer from light energy to heat and electrical energy.