Last week the price of crude oil reached an all-time high: 102 dollars a barrel! Bad news not only for us car-nuts, but it also set us thinking: why do we calculate the price of oil in a barrel that contains 42 US gallons or 159 litres? This seems strange as today a normal oil barrel contains 55 US gallons or 200 litres. Back the early days of petroleum buyers of petroleum brought their own barrels, for instance empty wooden whisky barrels. The price of petroleum was calculated per barrel and almost every kind of barrel was accepted as long as it was big enough for the buyer and not too big in the eyes of the seller. Needless to say this procedure soon caused friction between buyers and sellers and it was realized that a more serious method of calculation was needed. In August 1886 a group of producers in West Virginia got together and decided from then on to sell petroleum exclusively per gallon. And for every forty gallons the buyer would receive two gallons extra. Because the gallon was chosen (1 US gallon = 3.78 litres) the 42-gallon barrel became the standard. Today this still is the yardstick in which each drop of oil coming out of the ground is calculated, although nowadays it’s only a statistical size.







With thanks to Miel Citroen, Esso Archivist; photos Rutger Booy

March 6, 2008