I is for the idiosyncrasy of inches

Mary is every inch the schoolteacher.

While the metric system is very logical there’s something wonderfully daft about the United States customary systems of measurement:

1 inch = 254 millimeters, exactly
12 inches = 1 foot
36 inches = 3 feet = 1 yard
63,360 inches = 5,280 feet = 1,760 yards = 1 mile

Except for inches in a mile, I KNEW all of those by heart.

I love the etymology. “The English word inch comes from Latin uncia meaning “one-twelfth part” (in this case, one twelfth of a foot); the word ounce (one twelfth of a troy pound) has the same origin.”

Of course, I know it’s now 16 ounces = 1 pound = approximately 453.59237 grams.
And, confusingly, 16 fluid ounces = 2 cups = 1 pint = 0.5 quart = 0.125 gallon = approximately 0.473176 liter

“The vowel change from u to i is umlaut; the consonant change from c (pronounced as k) to ch is palatalisation.” But you knew that.

“In many other European languages, the word for ‘inch’ is the same as or derived from the word for ‘thumb’, as a man’s thumb is about an inch wide (and this was even sometimes used to define the inch); for example, Catalan: polzada inch, polze thumb; French: pouce inch/thumb; Italian: pollice inch/thumb; Spanish: pulgada inch, pulgar thumb; Portuguese: polegada inch, polegar thumb; Dutch: duim inch/thumb; Afrikaans: duim inch/thumb; Swedish: tum inch, tumme thumb, Danish and Norwegian: tomme / tommer inch/inches and tommel thumb; Czech: palec inch/thumb; Slovak: palec inch/thumb; Hungarian: hüvelyk inch/thumb.”

There are lots of sayings based on the US system. On one’s birthday, a child gets a “pinch for an inch,” to grow. A noted saying is “give someone an inch and they’ll take a mile”, which means that if you agree to part of what someone wants they will get, or take, ALL of what they want.

Then “every inch a” something means completely; in every way. “Mary is every inch the schoolteacher. Her father is every inch a gentleman.”

The great thing about the metric system is that you can always deduce the relationships – 1000 milliliters is a liter, 1000 grams is a kilogram, and the same is true for meters. But there’s something quaint about the measurement scale that was initially not only defined, but named, for people’s feet and fingers.