The human body is comprised of several ‘substances’ including.. Mercury, hydrogen hydroxide, fountain pens, the lost dates of calenders, various small woodland animals, including… Voles, rabbits & field mice. Other such things as… Misplaced birthmarks(of the brain) feelings of remorse and regret, the stolen trinkets of past lovers, and of course, white blood cells, pesticides, and the second hand from a 1956 ’hamilton railroad’ pocket watch.