Essex rivers

The Mighty Forest Buried in the Marshes

THE rivers of Essex are today mere streams compared with the rivers of 500 centuries ago; as they approach their wide estuaries they flow through marshland formed from soil brought down by their mighty forerunners. Along both banks of the Thames the marshes, little higher than the level of the sea, stretch far and wide, except fora few hundred yards at Purfleet and Grays, where the chalk breaks through their monotony.

The spring tides would often submerge them, and for centuries man has fought a battle with the waters blown upstream from the North Sea. The cost of embankments almost ruined the rich nuns of Barking, and it was not until the Dutch engineers came along in the 17th century that the Essex marshes could be profitably used by the farmer.

Since that time the marshes nearer London have become the sites of docks and industries, and another century or two will see London’s great Port actually within sight of the open sea.

Romantic as is this victory of man over Nature, there is a great romance of Nature herself beneath the river and the ancient marshlands through which it winds its way to sea. Here beneath the waters, with the ships sailing above them to the ends of the earth, are the fallen giants of our ancient forests. Here and there on our coasts we come upon a fossil forest, as at Lulworth, with trees turned to stone, but beneath the marshes of the Thames are submerged forests with trees that are still wood, as when, perhaps fifty or a hundred thousand years ago, men dressed in skins would hide among them hunting hyenas and bears.

From one of these lost forests has come down to us a dramatic piece of news. We know that one day a wild pig, seeking food in a forest where Carmarthen Bay is now, was killed by a great tree falling. The pig lay dead beneath the trunk for ages, buried deep in leaves and moss each year until the mould piled up through centuries of time, while empires rose and fell, and the forest sank slowly in the sea. One day they found in the marsh, among the trees embedded in the peat, the tree which fell and killed the pig at Lydstep Haven near Tenby.

It is a forest such as this that lies today beneath the marshes of the Thames, both in Essex and in Kent. If we sail down to Margate from London Bridge we sail where birds once nested in the tops of trees. The trees are gone, and our most ancient river has piled mud and sand high above the verdant glades, so that all we see are mud flats and a waste of waters.

This estuary of the Thames, with the country round it, was once eighty feet higher than it is. Southend and Sheerness were then far from the sea, up-river places, and where their busy streets are now were wooded hillsides, over which the stag and the wild boar roamed and men sent flint-headed arrows after them. Then the Thames wended its way through green vegetation where now is sea as far as the eye can reach. After passing the Nore, the comparatively narrow channel of the ancient river took a north-easterly course through either Black Deep or Barrow Deep, submarine depressions believed to be the sunken watercourse of the Thames, and entered the North Sea several miles east of Clacton. The Medway was then a tributary of the Thames, rather like the Darent now, while a range of hills extended north-east from Sheppey and far out to sea.

Beneath the marshy tracts bordering the great river from London to the sea these trees can be recovered by anyone prepared to dig a dozen feet. For over 250 years this vast submerged surface of ancient Britain, with its fossil treasures, has been opened up at one place and another. It was so in the days of Pepys in 1665, when he wrote in his diary:

At Blackwall, in digging the late docke, they did, twelve feet underground, find perfect trees covered with earth, nut trees with branches and the very nuts upon them; some of whose nuts Johnson showed us; their shells black with age, and their kernell upon opening decayed, but their shell perfectly hard as ever. And a yew tree (upon which the very ivy was taken up whole about it) which upon cutting, we found to be rather harder than the living tree usually is.

From Woolwich to Crossness Point, under the entire area of Plumstead and Erith Marshes, are oak and alder trees, branches and roots in great quantities. Furniture has been made out of the oak. On each side of the Thames beyond Purfleet and the Darent the stumps of the trees may often be seen. Beneath the marshes of Rainham and Dagenham, are vast numbers of trees with roots, boughs, and bark covered with mould and clay to a depth of from seven to twelve feet; the latest older than the Romans, the lowest as old as the Stone Age. From Greenwich to Greenhithe on the Kent side of the river an old forest bed of yew, oak, and pine lies twenty feet below, and beneath this bed two of our ancient ancestors have been found, one a hundred thousand years old and one thousands of centuries older.