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The passage makes the point that oil continues to be the chief fuel in certain areas ----.
Central heating, available in the US since the early
19th century, became popular only after the Civil
War. Typically, coal-burning furnaces fuelled the
early systems. The furnaces warped and cracked,
causing gases to escape, and had to be stoked
frequently. It took years and countless small
improvements, but by the mid-1920s the systems
had become reliable and, with the emergence of oilfired
furnaces, more convenient. Natural gas, which
became widely available with the building of a
pipeline infrastructure after World War II, had
developed into the leading fuel by 1960. Its
acceptance resulted in part from its versatility - unlike
oil, it can power appliances such as clothes washers
and dryers, ovens, ranges and outdoor grills.
Because it comes primarily from US and Canadian
fields, natural gas is also less vulnerable than oil is,
to war and embargo. Oil remains the predominant
fuel in a few areas, such as New England, where
natural gas pipelines have not yet thoroughly
penetrated. Oil users in many regions have the
advantage of being able to buy a season's supply in
advance at favorable rates and, in contrast to most
gas users, can easily change their supplier.