Henry De la Beche and William Logan, between 1836 and 1841, conducted considerable research on the hills of Town Hill and Kilvey (Cilfái) in Swansea. Understanding the dip of the sandstone beds and the coal veins that ran through the rock helped both men understand the relationship between the Pennant Sandstone and the coal seams that Swansea was built upon. Kilvey has a coal mining history extending back at least a thousand years.
This exposure of weathered sandstone would have been examined by William Logan and both men would undoubtedly have discussed it as they worked to understand the more complex geology of Town Hill and northern Swansea. You can see the rock here dips down. In fact, it dips at about forty degrees to the north, which means that coal seams exposed on the surface on Kilvey would be hundreds of metres underground by the time you reached Morriston. Beche and Logan were trying to understand how and where to find those deep coal veins to allow better locations for new coal mines.
The layers of sandstone and siltstone are very thin here, and centuries of atmospheric pollution have highlighted the separate layers. Other parts of Kilvey have thick beds of stone used to build the Prince of Wales Dock and the Port Tennant houses.
My next book is about the work of these two men and how they worked to understand the veins of coal that were so important to Swansea in the nineteenth century.
Nigel Robins 