Anthracite iron charcoal — long the fuel of preference for smelting and glass making, creating a decades long search for alternative fuels. By mid-1792 prominent Philadelphians had formed the Lehigh Coal Mine Company (LHCM Co.) to bring Anthracite to cities reachable via the Delaware River Valley, especially Philadelphia — the nation's largest and most industrialized city, though no one fully understood how to use anthracite as a sole fuel—just that "it 'could' burn 'some' of the time" with a hot enough base fire, so could augment furnace fuels. The LHCM Co. had great difficulty getting many ark-loads of coal to the docks
Anthracite iron not keep the furnace in operation for more than two months. While distinguished visitors, including Governor Joseph Ritner, acknowledged his success, he sold out his share in Valley Furnace and went to New York City. The research was proceeding along parallel lines across the Atlantic. George Crane, owner, and David Thomas, superintendent of the Yniscedwyn Iron Works, had themselves conceived of the idea of using hot blast to smelt anthracite. Thomas was sent to Scotland to examine Neilson's installation and reproduced it at Yniscedwyn. Crane filed for a British patent on smelting iron with anthracite and hot blast in 1836