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
What is a Masterpiece? confluence of memories and emotions forming a single idea", that it has "a power of recreating traditional forms so that they become expressive of an artist's own epoch and yet keep a relationship to the past". The highest masterpieces are said to be "illustrations of great themes." Clark also implicitly excluded the erotic from considerations of what constituted a masterpiece, based on his perspective that a necessary condition is the balance between sense and form (works that are too sensual are, therefore, unbalanced and not to be categorised at masterpiece level). What is a Masterpiece? What is a Masterpiece? is