You can read Newton's biography online at the Royal Society Website. Archaeologist and biographer William Stukeley in 1752, told the famous story as told to him by a young Isaac Newton. "We went into the garden and drank thea, under some apple trees... he told me he was just in the same situation, when the notion of gravitation came into his mind. 'Why should that apple always descend perpendicularly to the ground,' thought he to himself."