where did the term proof for alcohol come from
Alcohol proof The term proof dates back to 16th century England, when spirits were taxed at different rates depending on their alcohol content. Spirits were tested by soaking a pellet of gunpowder in them. If the gunpowder could still burn, the spirits were rated above proof and taxed at a higher rate.[1] As gunpowder would not burn if soaked in rum that contained less than 57.15% ABV, rum that contained this percentage of alcohol was defined as having 100 degrees proof.[2] The gunpowder test was officially replaced by a specific-gravity test in 1816.[1]
Toast (honor) According to various apocryphal stories, the custom of touching glasses evolved from concerns about poisoning. By one account, clinking glasses together would cause each drink to spill over into the others' (though there is no real evidence for such an origin).[2] According to other stories, the word toast became associated with the custom in the 17th century, based on a custom of flavoring drinks with spiced toast. The word originally referred to the lady in whose honor the drink was proposed, her name being seen as figuratively flavoring the drink.[3][4] The International Handbook on Alcohol and Culture says toasting "is probably a secular vestige of ancient sacrificial libations in which a sacred liquid was offered to the gods: blood or wine in exchange for a wish, a prayer summarized in the words 'long life!' or 'to your health!'"[5]