AT the time when a Committee of the Royal Society entrusted me with the preparation of a sketch of the geological facts bearing upon the great volcanic eruption of Krakatao in 1883, I was quite unaware that any reliable records concerning the early history of the East Indian Archipelago were in existence. I stated, therefore, that authentic history commenced only about three centuries ago, when the district began to be visited by the Dutch and Portuguese navigators; and that the earliest eruption of which we have any detailed account was that of 1680, described by Vogel and Hesse.1