Atmosphere of Venus water and subsequent rise of the levels of other greenhouse gases. Despite the harsh conditions on the surface, the atmospheric pressure and temperature at about 50 km to 65 km above the surface of the planet is nearly the same as that of the Earth, making its upper atmosphere the most Earth-like area in the Solar System, even more so than the surface of Mars. Due to the similarity in pressure and temperature and the fact that breathable air (21% oxygen, 78% nitrogen) is a lifting gas on Venus in the same way that helium is a lifting gas on
Natural gas in the United States sealed with rope and molten lead. In the 1800s and early 1900s, most natural gas discoveries were made while exploring for oil. Natural gas was usually an unwanted byproduct of oil production. In the 1870s steel pipe replaced cast iron. In 1883, Pittsburgh became the first major city supplied with natural gas. Other cities followed, but only if they were close to natural gas wells. Because natural gas was a byproduct, it was priced cheaply, and, where available, undercut the market for town gas. In 1891, one of the longest pipelines of the time was built, a 120-mile long pipeline