Anthracite iron as an ingredient into a reverberatory furnace (and in later years, a Bessemer converter). Anthracite, also known as stone coal or rock coal, is very difficult to ignite, mine, clean, and break into smaller chunks and requires correct conditions to build heat or hold temperature and sustain burning—which oft depend upon the size and uniformity of the coal particles. Yet American cities were cramped for fuels, woodlands were exhausted near bigger towns and Philadelphia, largest city in America needed fuels for mills and foundries as well to sustain manufacturing. Inventor and industrialist Josiah White (owner of a wire mill, foundry
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