Gothic Revival

This weekend Notre-Dame Cathedral is opening its doors once again, more than five years after a fire razed the roof of the iconic Gothic cathedral. Beyond its architectural beauty, Notre-Dame has a rich history. Its cornerstone was laid by Pope Alexander III in 1163. It housed the Crown of Thorns relic brought to Paris by King Louis IX about 1238. It was briefly redubbed a Temple of Reason during the French Revolution. And it hosted the coronation of Napoleon I in 1804.
The 861-Year History of Notre-Dame de Paris
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An Anatomy of Its 2019 Fire
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Concept of Proof

Today marks the anniversary of the day Prohibition died. On December 5, 1933, the Twenty-first Amendment was ratified, relegalizing alcoholic beverages in America after a 14-year dry period. The repeal meant that—after years of sometimes-dangerous bootleg liquor in the marketplace—alcohol could again be regulated. But the history of alcohol regulation has its own share of ambiguity.

Alcoholic beverages bottles at Host 2013, international exhibition of the hospitality industry on OCTOBER 18, 2013 in Milan. Bullet proof

One way that alcohol content is measured is by proof—a measurement that varies from country to country. The proof measurement harks back to 16th-century England, when the government would put an extra tax on “proof spirits”—liquor that contained a certain higher amount of alcohol. The English government would test the amount of alcohol content in a liquor by soaking a gun pellet with it and attempting to light the wet pellet on fire. If it could be lit, the alcohol was a proof spirit.

Volume level

Another way to measure alcohol content is alcohol by volume (ABV), which quantifies the percentage of alcohol in the overall liquid—a standard international measurement. England refined its proofing method in 1816 with a formula that set the threshold of a proof spirit at about 57.06 percent ABV. But when the alcohol industry took hold in the U.S., Americans took a different approach. Stateside, a liquor’s proof is two times the ABV, meaning that a beverage with 30 percent ABV is 60 proof. In the U.S., a “proof spirit” has to be at least 100 proof.

French translation

The simplest proof scale, however, is the one used in France, developed by scientist Joseph-Louis Gay-Lussac in 1824. Gay-Lussac took 100 percent ABV to equal 100 proof and 100 percent water by volume to be 0 proof. This means that the ABV percentage number is the same as the proof number. So, to compare the three systems, an alcohol with 45 percent ABV is about 78.9 proof in Great Britain, 90 proof in the U.S., and 45 proof in France.

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