Flamsteed discusses the position of the Earth's perihelion at the time of the Deluge. He states his belief, based on twenty years of his observations of Mercury and Mars, that Earth's aphelion 'is carried forward... annually... under the fixed stars'. Flamsteed argues for a date for the Deluge earlier by a century than that suggested by Whiston and condemns Whiston's theory [of the Deluge] in general.