Before the nineteenth century, the technology wasn’t available to measure the alcohol content of liquids accurately. The first hydrometer was invented by John Clarke in 1725 but wasn’t approved by the British Parliament for official use until the end of the century. In the meantime, purveyors of spirits needed a way to determine alcohol content, and tax collectors demanded a way to ascertain exactly what their rightful share of liquor sales was. So the British devised an ingenious, if imprecise, method. Someone figured out that gunpowder would ignite in an alcoholic liquid only if enough water was eliminated from the mix. When the proportion of alcohol to water was high enough the black gunpowder would explode- this was the proof of the alcohol. The British proof, established by the Cromwell Parliament, contained approximately eleven parts by volume of alcohol to ten parts water. The British proof is the equivalent of 114.2 U.S. proof. More potent potables were called “over proof” (or o.p.), and those under 114.2 U.S. proof were deemed “under proof” (or u.p.) The British and Canadians are still saddled with the archaic method of measuring alcohol content. The United State's system makes a slightly more sense. The U.S. proof is simply double the alcohol percentage volume at 60 degrees F. For once, the French are the logical nation. They recognize the wisdom in bypassing “proof’ and simply stating the percentage of alcohol on spirits labels. The French method has spread to wine bottles every where, but hard liquor, true to its gunpowder roots, won’t give up the “proof”. Submitted by Robert Abrams, of Boston Mass |
