35 Oil Refining
An important new industry, oil refining, grew after the Civil War. Crude oil, or petroleum -- a dark, thick ooze from the earth -- had been known for hundreds of years, but little use had ever been made of it. In the 1850s Samuel M. Kier, a manufacturer in western Pennsylvania, began collecting the oil from local seepages and refining it into kerosene. Refining, like smelting, is a process of removing impurities from a raw material. Kerosene was used to light lamps. It was a cheap substitute for whale oil, which was becoming harder to get. Soon there was a large demand for kerosene. People began to search for new supplies of petroleum. The first oil well was drilled by E. L. Drake, a retired railroad conductor. In 1859 he began drilling in Titusville, Pennsylvania. The whole venture seemed so impractical and foolish that onlookers called it Drakes Folly . But when he had drilled down about 70 feet , Drake struck oil. His well began to yield 20 barrels of crude oil a day. News of Drakes success brought oil prospectors to the scene. By the early 1860s these wildcatters were drilling for black gold all over western Pennsylvania. The boom rivaled the California gold rush of 1848 in its excitement and Wild West atmosphere. And it brought far more wealth to the prospectors than any gold rush. Crude oil could be refined into many products. For some years kerosene continued to be the principal one. It was sold in grocery stores and door-to-door. In the 1880s refiners learned how to make other petroleum products such as waxes and lubricating oils. Petroleum was not then used to make gasoline or heating oil.
GMAT数学精华题型解析(4)
GMAt,GMAt考试,GMAt数学
GMAT考试备考综合经验分享:数学
GMAT数学考试晋级技巧之:排列组合
GMAT数学精华题型解析(5)
GMAT数学考试晋级技巧之:几何问题
GMAT数学考试常用理论总结
GMAT数学常用词汇及概念汇总(八)
名师推荐:GMAT数学必备词汇大全(其它平面图形、立体图形)
GMAT数学精华题型解析(11)
GMAT数学备考指导:常用理论小结
名师推荐:GMAT数学必备词汇大全(计量单位)
GMAT数学常用概念总结
名师推荐:GMAT数学必备词汇大全(坐标)
GMAT数学备考经验总结(I)
ST官方指南写作满分范文4
GMAT数学备考重点总结
GMAT数学词汇:分数、小数
GMAT数学晋级技巧之独立重复性试验总结
GMAT数学备考指导:数学基础
GMAT数学精华题型解析(1)
浅析GMAT数学考试应对技巧
GMAT数学考试中问题求解题型的解题思路
GMAT数学常用词汇及概念汇总(七)
GMAT数学精华题型解析(8)
名师推荐:GMAT数学必备词汇大全(单位类)
GMAT数学考试晋级技巧:高分突破技巧
写作技巧分享:Writing Tips from Oakley Hall
详解GMAT数学考试高分策略
GMAT数学精华题型解析(2)
不限 |
英语教案 |
英语课件 |
英语试题 |
不限 |
不限 |
上册 |
下册 |
不限 |