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Britain's mining and quarrying industries date back to the Stone Age flint mines of 2500 BC and still exist. In that period of more than 4,000 years the country's miners have produced colossal amounts of copper, tin, lead, zinc, iron, a lot of silver and some gold, and smaller amounts of just about every other metal from arsenic to uranium. The metals were the foundation of our industrial wealth and ease of living but they were driven by King Coal, which at its peak employed a million men and produced more than 200 million tons a year. Granite from Scotland, limestone from Southern England, sa

AbstractThe use of aircraft carriers in offensive operations in waters where an enemy can deploy strong air forces is the subject of much debate, and it is sometimes asserted that the carriers could not survive long enough to discharge a mission. This article analyzes that proposition and shows that a wide range of possible outcomes exists, depending on the carrier commander's actions.By considering the fundamental mechanics of the problem, a number of options for technological improvement are suggested, and it is shown that they have widely differing, and sometimes very unexpected, effects on the outcome.The model requires a blend of discrete and continuous modeling, the main features of which are discussed in the Appendix.