William Haseldine Pepys, Transactions of the Geological Society (1811)
“ I was engaged a few years ago in a course of experiments on hydrogen gas, which was procured in the usual method, by the solution of iron turnings in diluted sulphuric acid. The sulphate of iron hence resulting, to the amount of some quarts, was poured into a large earthen pitcher, and remained undisturbed, and unnoticed for about a twelve month. ”
