Albert Smith, The Marchioness of Brinvilliers… (1886)
“ Then dropping some colourless fluid into them, one after the other, a precipitate fell down in all, in clouds of the brightest tints, but each different. ‘See how completely these dull minerals do my bidding,’ he exclaimed. ‘To you the potion offers no trace by which its nature could be told; to me there is not an atom suspended in it, in its invisible but imperishable form, which cannot be reproduced before our eyes. ”
