I.P. Factly

“The idea of the Solar System dates back to 250 BC when Aristarchus of Samos suggested that the planets revolved around the Sun. This is called the heliocentric model, and was largely ignored until astronomer Nicolaus Copernicus confirmed it during the sixteenth century.”
― IP Factly, 101 Facts... Solar System

“In his will, Washington left strict orders that all the slaves he owned outright were to be freed after his wife's death. Older slaves, particularly his retired personal servant William Lee, with him through war and peace, were to be cared for the rest of their lives. Younger slaves whose family could not support them were to remain in service until age twenty-five. The youngsters were to be taught to "read & write; and to be brought up to some useful occupation".   More than $10,000 was eventually paid from Washington's estate in pensions to former slaves.   Of the nine early presidents who owned slaves, he was the only one to set his slaves free. This final act is perhaps the best summary of his greatness. While other men talked of liberty, Washington took action to bring it about.”
― IP Factly, George Washington – Just the Facts! Amazing Facts and Photos - Biography Books for Kids.