Turning attention to the price data, we may note first how expensive whale oil was in comparison with the crude oil that replaced it. Even at its lowest historical prices, in the 1820s, the least expensive type of oil (whale oil) was priced at more than $200 (2003$) a barrel (42 gallons). At its highest price level (1855) Sperm Whale oil sold at more than $35 (2003$) a gallon, namely almost $1500 (2003$) a barrel (!). This tells us something about how difficult it may be to substitute fossil fuels with "biofuels" (bio-ethanol, bio-diesel, or other). Without the support of fertilizers, irrigation, transportation, and agricultural machinery, which all depend on fossil fuels, biofuels would probably cost as much today as whale oil did in the 19th Century. It also shows what an incredible bonanza crude oil has been. When kerosene became first available in the 1860s, a barrel of crude oil sold for some $90 a barrel in to-day's money (data from
www.wtrg.com). In the 1870-80s it had already fallen to values in the order of $20 (2003$) a barrel, comparable with modern prices.