A "hand" is a unit of measurement commonly used in the context of measuring the height of horses. In the United States and some other English-speaking countries, a hand is defined as exactly 4 inches or 10.16 centimeters.
Horses are typically measured in hands from the ground to the highest point of their withers (the ridge between the shoulder blades). This measurement is a convenient way to describe a horse's height without relying on feet and inches or meters.
For example, a horse that measures 15.2 hands is 15 hands and 2 inches tall. Horses can vary in height, and the hand system provides a standardized way to communicate a horse's size, which is particularly important in horse racing, equestrian sports, and the horse industry in general.
A "barleycorn" is a small unit of length that was historically used for measuring small lengths or sizes of objects, particularly in some English-speaking countries. It is based on the length of an average grain of barley.
In the traditional English system of measurement, one barleycorn is equal to approximately 1/3 of an inch or about 0.8467 centimeters. This unit was used for measuring short lengths, such as the length of a person's foot for shoe sizing.
While the barleycorn is not commonly used in modern times for scientific or everyday measurements, it has historical significance, especially in the context of footwear sizing. Some traditional shoe sizing systems still reference barleycorns, where each size increase or decrease corresponds to the length of a barleycorn. However, most modern countries have adopted standardized shoe sizing systems based on centimeters or inches for more precise and consistent measurements.