Henry Ernest Dudeney/Modern Puzzles/184 - A Prohibition Poser

by : $184$

 * A Prohibition Poser
 * Let us now take another step and look at those cases where we are still allowed any amount of waste,
 * though the liquid is now limited to a stated quantity.


 * The American Prohibition authorities discovered a full barrel of beer,
 * and were about to destroy the liquor by letting it run down a drain
 * when the owner pointed to two vessels standing by and begged to be allowed to retain in them a small quantity for the immediate consumption of his household.
 * One vessel was a $7$-quart and the other a $5$-quart measure.
 * The officer was a wag, and, believing it to be impossible, said that if the man could measure an exact quart into each vessel
 * (without any pouring back into the barrel) he might do so.
 * How was it to be done in the fewest possible transactions without any marking or other tricks?
 * Perhaps I should state that an American barrel of beer contains exactly $120$ quarts.