From ancient times to the 19th century, the same unit of measurement could have different values ​ ​ not only in different countries, but also in different cities of the same country! So, in Austria in the 15th century, almost every city and even every significant market had its own measures. In Germany, attempts to streamline the system of measures began in the early Middle Ages, but did not lead to anything until the end of the 19th century. In France in the XIV century, an attempt to introduce the same measures throughout the state failed due to the resistance of sovereign princes and bishops. Neither Louis XI in the 15th century nor Louis XVI at the end of the 18th century could also bring measures to uniformity... Only in 1875, an international agreement was finally signed in Paris - the "metric convention" to ensure international uniformity of measurements and improve the metric system of measures. Sometimes, reading books or articles on the Internet, we are faced with incomprehensible units of measurement of different countries and times. Inquisitive people immediately have questions: The pirate drank a pint of beer - how many in liters? Thumbelina got her name from the word "inch," so how tall was this fabulous baby? Bigfoot Man - Bigfoot got the name for his enormous leg size, and what is he, a mere foot? How does the nautical mile differ from the land mile? How much is an oblique fathom in the shoulders? How does it differ from a fly fathom? Eat a pound of salt - how much? And a bunch of other questions about measurement measures, which you will find answers to in this book.