Paper, 'De la naturaleza de la piedra baazar' [On the nature of the 'baazar' stone] by John Evelyn Evelyn describes a medical ritual involving a stone, which occurs in Persia and on a small island near India, in which the stone is ground up like flour and poured into the mouth, or dipped in water and rubbed on a white cloth. Subject: Medicine Read to the Royal Society on 25 March 1680 March 1680