Encouraged by these developments, Ralph Brandling's son, Charles Brandling, firstly commissioned more extensive mining of near-surface coal on his estate and then, encouraged by the discovery of several strata below his estate, began boring operations in 1758 to allow ultimately for deeper coal extraction. The result was the opening of Felling Colliery in 1779, working on the High Main stratum at a depth of 125 fathoms. A brown paper mill was also opened in 1798. Felling mining disasters On 19 January 1811, the original High Main seam at Felling Colliery was closed, but by that time the colliery had grown enormously. The colliery was deepened to reach the Low Main seam. Two shafts were provided: John Pit and William Pit. The Low Main and began operation in October 1810. Disaster struck Felling Colliery on 25 May 1812 when, despite the colliery containing the most up-to-date safety measures, firedamp ignited and at around 11.30 am, "one of the most tremendous explosions in the history of coal mining took place". Two explosions rocked the colliery, the blast appearing in both pits. A cloud of coal dust and debris over a radius of a mile and a half was ejected from the colliery. One account recalled: Immense quantities of dust and coal rose high into the air in an inverted cone...In the village of Heworth, this cloud caused a darkness like that of early twilight and covered the roads so thickly that the footsteps of passengers were deeply imprinted in it. As soon as the explosion was heard, wives and children of the workmen ran to the pit. Wildness and terror were pictured in every countenance. The crowd soon collected to several hundreds, some crying out for a husband, others for a parent or a son, and all affected by a mixture of horror, anxiety and grief. Following the first blast at 11:30, rescue attempts started at 12:15. At 14:00 the second blast occurred and no further rescues occurred. Some 29 men were saved, but the remaining 92 men and boys were killed. Two days later the decision was made to seal the colliery to starve the fire of oxygen. Just one year later, on 24 December 1813, a further catastrophe occurred: About half-past one o'clock on the morning, an explosion took place in Felling colliery, by which nine men and thirteen boys were hurried into eternity, several others severely burnt, and all