Using the word as a unit of measurement, “cord” is traced back to the 1610s when wood was sold in bundles tied with a, you guessed it, cord. Today, it is well recognized that a cord of firewood must take up 128 cubic feet, traditionally in a stack 8′ x 4′ x 4′. As with other units of measurement, the size of a cord of wood is typically regulated, either by a state or national government.
A measure of depth, fathom is derived from either or both the Old English word faeom or the Old Saxon word fathmos, both meaning the length of the outstretched arms. Like the other measurements, it was eventually standardized, this one to the length of two yards, which is approximately how far it is between the tips of a man’s fingertips when his arms are extended. Although international nautical charts have converted to meters, in the United States, measuring depth with fathoms and feet is still in vogue.
Derived from the old French words boissel and boisseau, a bushel is a measure of dry goods, typically grains, equal to about eight gallons (or four pecks). Today, it is most commonly used to measure things by their weight, and that weight varies depending on the commodity measured. Typical goods sold by the bushel (and their weights) include oats (32lb), malted barley (34lb), corn (56lb), wheat (60lb) and soybeans (60lb).
How many pickled peppers did Peter Piper pick? It turns out, by peck, Peter picked about two gallons worth of peppers. Peck probably derived from the Old French, pek or picot, and is also a measure of dry goods or commodities. Some retailers, farmers at markets and roadside stands still sell fruits and vegetables by the peck, particularly during canning season; however, it is much more common today to find them sold by either the quart or the pound.
Know has been uses to measure the speed of a ship since the 1630s. Knot derives from the word of the same spelling meaning “intertwined ropes”. To measure speed back in the day, a long rope had knots tied regularly, about every 50 feet, and a log tied to the end. The log was dropped into the water and a sandglass upended at the same time to time how many knots per time unit. Eventually, the speed of one knot became standardized at one nautical mile (6076 feet) per hour.
The baby of the bunch, the measurement Mach was named after Ernst Mach and coined in 1937. Not really a measure of speed, the Mach numbers represent the ratio of the speed of an object moving through a fluid (a gas, like the atmosphere, can be a fluid here) and the local speed of sound. With Mach numbers between 1.2 and 5, supersonic vehicles like the F-104 Starfighter and the Concorde travel at speeds between 915 and 3840 miles per hour. When the Space Shuttles re-entered the atmosphere, they initially traveled at a speed greater than Mach 25!
From Today I Found Out, which has related articles:
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