Petroleum petra

The word petroleum is de rived from the Latin words for rock (petra) and oil (oleum)... 

Throughout human history, people have collected petroleum to burn in lamps to provide light. They found petroleum seeping from cracks in rocks in certain locations. In fact, the word petroleum literally means "rock oil" and is derived from the Latin words for rock petra) and oil oleum). In the 19th century, as the U.S. entered the machine age and its population increased, the demand for petroleum to produce kerosene for lighting and as a machine lubricant also increased. Because there was no reliable petroleum supply, Edwin Drake drilled the first oil well in the United States near Titusville, Pennsylvania in 1859. The oil industry flourished for a time, but when Edison introduced the electric light in 1882, investors feared that the industry was doomed. However, the invention of the automobile in the 1890s soon revived the industry on a massive scale. 

Petroleum (rock-oil, derived from Latin petra, meaning rock or stone, and Latin oleum, meaning oil) occurs widely in the earth as a gas and a liquidJ Petroleum is a mixture of gas, liquid, and solid hydrocarbon-type chemical compounds that occur in sedimentary rock deposits throughout the world. In the crude state, petroleum has minimal value, but when refined, it provides high-value liquid fuels, solvents, lubricants, and many other products. 

Petroleum is perhaps the most important substance consumed in modem society. It provides not only raw materials for the ubiquitous plastics and other products but also fuel for energy, industry, heating, and transportation. The word petroleum, derived from the Latin petra and oleum, means literally rock oil and refers to hydrocarbons that occur widely in the sedimentary rocks in the form of gases, liquids, semisoUds, or solids. 

Petroleum is a complex mixture of hydrocarbons formed over eons of time through the gradual decay of buried animal and vegetable matter. Crude oil is a viscous black liquid that collects in vast underground pockets in sedimentary rock (the word petroleum literally means rock oil, from the Latin petra, rock, and oleum, oil). It must be brought to the surface via drilling and pumping. To be most useful, the crude oil must be refined. 

The term petroleum comes from Latin petra for rock and oleum for oil, and literally means rock oil. In China, since 1008 c.e., crude oil has been called shiyou, which means rock (sfe) oil (you). The earliest known extraction of petroleum was before 2000 b.c.e. from oil pits near Babylon, in modern Iraq, for use as asphalt for city walls. 

---