Rod

Q From Nichole: When reading American Western History written by people of that period you will run into the word rod, used in reference to distance. For example: ‘After drinking a bottle of Indian whiskey he was unable to walk even a rod’. What is the measurement of a rod? Where did the term come from?

A A rod is indeed a unit of measurement, 16.5 feet or 5.5 yards. It is also known as a pole or — especially in the USA — a perch, so leading to that euphonious set of measurements that were printed on the back of every child’s exercise book when I was young: “rod, pole or perch”, which we used to delight in quoting, though none of us had come across any of them in the real world.

The rod was one of an important set of measures that were subdivisions of the standard mile. Four rods equal one chain (22 yards — still the length of a British cricket pitch between the stumps), 40 rods make one furlong and 320 rods equal one mile.

The name comes from the use of a rod as a measuring stick (quite a big one, you may agree ...). It’s first recorded in the fifteenth century; pole dates from about the same period.

Perch to many people is the name of a fish, but in medieval English it also meant much the same as pole, being derived via French from the Latin pertica for a long staff or measuring rod (it’s the same word as the wooden rod your cage bird stands on). It’s also used as the name for a square measure for small plots of land: 160 perches make an acre. And completists might like to note that a perch is also an old volume measure for masonry: 24.75 cubic feet.