?????????“??????”???????????????????????????????????????????????????????????????? ??, ???, ??, ??, ?? ?? ??? ??? ??? ?? ??? ?? ? ???, ?? ??? ???? ????. ??????René Descartes's sketch of how primary and secondary rainbows are fashioned, Discours de la Méthode, 1637. Descartes' 1637 treatise, Discourse on System (Discours de la Méthode), more S