The Trimmer family ran a brickworks in Brentford (across the River Thames from Kew) for over a century. Digging for clay unearthed fossils and other interesting oddities. Under the watchful eye of Joseph Banks, William Kirby Trimmer (1770—1811), built up a collection, or cabinet, of such finds. His report on the stratigraphy of two fields and the fossils that had been discovered there was published posthumously in the Philosophical Transactions of the Royal Society in 1813. At the time, few such sources of fossils around London were known.
Here is his description of the first field:
The first field is about half a mile north of the Thames at Kew bridge; its surface is about twenty-five feet above the Thames at low water. The strata here are first, sandy loam from six to seven feet, the lowest two feet slightly calcareous. Second, sandy gravel a few inches only in thickness. Third, loam slightly calcareous from one to five feet; between this and the next stratum, peat frequently intervenes in small patches of only a few yards wide, and a few inches thick. Fourth, gravel containing water; this stratum varies from two to ten feet in thickness and is always the deepest in the places covered by peat; in these places the lower part of the stratum becomes an heterogeneous mass of clay, sand, and gravel, and frequently exhales a disagreeable muddy smell. Fifth, the main stratum of blue clay, which lies under this, extends under London and its vicinity, the average depth of this clay has been ascertained by wells that have been dug through it, to be about two hundred feet under the surface of the more level lands, and proportionably deeper under the hills, as appears from Lord Spencer’s well at Wimbledon, which is five hundred and sixty-seven feet deep…
In the fourth stratum were found teeth and bones of both the African and Asiatic elephant, teeth of the hippopotamus, bones, horns, and teeth of the ox. A tusk of an elephant measured, as it lay on the ground, nine feet three inches, but in attempting to remove it, it broke into small pieces.
He then gives the location and stratigraphy of the second field, and continues:
In the first stratum, as in the other field, no organic remains have been observed. In the second, but always within two feet of the third stratum, have been found the teeth and bones of the hippopotamus, the teeth and bones of the elephant, the horns, bones, and teeth of several species of deer, the horns, bones, and teeth of the ox, and the shells of river fish
The remains of hippopotami are so extremely abundant, that in turning over an area of one hundred and twenty yards in the present season, parts of six tusks have been found of this animal, besides a tooth and part of the horn of a deer, part of a tusk, and part of a grinder of an elephant, and the horns with a small part of the skull of an ox.
Who knew that hippopotami were once “so extremely abundant” on the Thames?
Apparently, hippos and elephants did roam around London during the delightfully-named Ipswichian interglacial period about 125000 years ago when the climate was more balmy. Maybe it’s time to bring them back: But Yes the Hippopotamus.
* With apologies to Sandra Boynton.