"1. There was a time when the organic body was alive at the bottom of the sea.
"2. It was afterwards imbedded in the cretaceous deposit.
"3. It became petrified; a very slow process.
"4. The Chalk was, by some change of marine currents, washed away, or degraded, [i. e. worn away under the atmosphere by the weather and casualties, a process slow almost beyond description,] and the solid flints and fossils [thus detached from their imbeddings], were rolled into shingles.
"5. Afterwards, these shingles were covered up, and buried under Tertiary deposits.
"In this way of interpretation, a section of a few perpendicular feet indicates a long lapse of time, and the co-ordinate fact of the entire change of organic types, between the beds above and those below, falls in with the preceding inference, and shows the lapse of time to have been very long."[50]