The Gunpowder story

The Glyn-neath Gunpowder Works, or Powder Mills, were established near Pontneddfechan in 1857 to produce blasting powder (known as black powder) for use in coal mining and limestone quarrying. The works operated until 1931.

This steep sided valley might seem a strange place to build and operate a manufacturing business, however, the location was actually well suited to the dangerous process of manufacturing gunpowder. The site was large and remote, stretching over a mile and a half along the north bank of the River Mellte, with room to create plenty of space between each factory building to ensure that any explosions were localised.

There was also free energy on tap – the River Mellte powered the factory's waterwheels and turbines – and raw materials (charcoal, sulphur and salt petre or potassium nitrate) could mostly be sourced in the vicinity. The topography of the valley was very useful, too. The factory was built into the steep slopes with large banks between buildings, to stabilise them and reduce the impact of explosions. And despite its remote location, Pontneddfechan was well connected to transport links including the Neath and Swansea Canal and the Vale of Neath Railway.

Raw materials came in at the bottom of the site and were transported around by tramroad until the finished black powder came out at the top. The quality of the black powder was tested by using it to fire a cannon which is now outside Brecknock Museum in Brecon. Only if the powder propelled a cannon ball a specific distance did it make the grade.

Safety was paramount and all possible precautions to avoid explosions were taken. Employees had to change into work clothes before entering potentially dangerous areas. They wore leather slippers fastened with wooden pegs over their shoes and boots. Trousers were not allowed pockets or turn-ups to prevent grit to be carried into the works in case it caused sparks.

Large areas of the works were regularly dowsed with water to keep them damp in a process called liquoring. If an explosion occurred in one building other areas of the works would automatically be drenched to prevent the explosion spreading. Despite these precautions many explosions were recorded.