Geology Site Account

Historical site only

In the early nineteenth century, before any of the modern sea defences were constructed along the northern shore of the Thames estuary, the cliffs of London Clay were subject to extensive coastal erosion. As a result, the hard septarian nodules that are contained in the London Clay accumulated on the foreshore in considerable quantities.

In the past, particularly in the Roman period, these nodules were a useful source of building stone but in the early nineteenth century they were used for the manufacture of Roman cement which was very popular before the invention of Portland cement in 1850. Roman cement was used for most of the purposes for which Portland cement is used today and there was therefore a great demand for it. It was a very rapid setting hydraulic cement, which set hard even underwater. Much of the waterproof external rendering known as stucco used during the Regency period was made from this cement.

Harwich was the main centre of this industry but there was also a cement factory at Leigh-on-Sea. The Leigh factory was supplied with the nodules, known as cement stones, from the shores nearby and also from Southend and Shoebury. Men were employed to gather them at low tide and often located them by probing the sand with iron rods, a practice that led to litigation and was eventually stopped by the land owners because of the fear of increasing coastal erosion.

According to local Post Office directories the cement factory (operated by David Montague) was in operation in 1840 but by 1845 it had moved to Stratford.