## The Smoot Unit turned 50 years old last week.

You can read all about that at the Laughing Squid in a nice little article by Dave Schumaker written October 3, 2008. The article has a photo of the earmaking event--the Harvard Bridge was measured to be 364.4 smoots and an ear--when the world acquired the unit of measure that would be known as "the smoot unit." (http://laughingsquid.com/celebrating-50-years-of-the-smoot/)

You may also read about the Smoot unit's 50th birthday at Chance and Necessity, where randomness and regularity meet

(http://chancenecessity.blogspot.com/2008/10/smoot-smoot-smoot.html).

Oliver Smoot, for whom the unit is named, has retired. You can listen to an interview with him that was given December 7, 2005 for National Public Radio. A blurb about the interview on their website says: Oliver Smoot is retiring from his chairmanship of the American National Standards Institute. He lent his name -- and body -- to the "smoot" -- a unit of length, equal to his height (5 feet, 7 inches).

(http://www.npr.org/templates/story/story.php?storyId=5043041)

Ransom Riggs has already written a fine article about unusual units of measure and you can read about that at www.mentalfloss.com. Riggs writes about the **Warhol** unit of fame (15 minutes), the **mickey**(the smallest measurable movement of a computer mouse), and the **pinkwater** (measure of chair comfort). (http://www.mentalfloss.com/blogs/archives/16540).

In my line of work as a medical transcriptionist, I come across some strange measurement units. The metric system is used in science and medicine and seems on the surface to be all orderly and neat. Ten is such a nice even number that can be written with just two digits, if you call the placesaver zero a digit. With metric system you can count all sorts of things--lengths, volumes, dry things, wet things, speed, time, tiny things, huge things, and everyone can have an equal chance of knowing exactly what the numerals mean. That is so foreign to those of us who use the standard measures of America--inches, feet, yards, miles; teaspoons, cups, pints, quarts, bushels; ounces, pounds, tons; gallons; acres, townships. Those of us who cook on a regular basis know exactly what is meant when a recipe calls for a pinch, dollop, smidgen, dash, or says to "season to taste."

The scientific world, as neat and ten-based as it is, gets a little messy in its metrics when certain kinds of measurements are named after people and used to measure real-life things. In my work I commonly encounter the **Hounsfield** unit (HU), the **Curie** (Ci), the **joule** (j), the **tesla** (T), and others. Sir Godfrey Newbold Hounsfield, Marie or Pierre Curie, James Prescott Joule, and Nikola Tesla gave their names for those.

If you want to get picky about it, 1 Ci = 3.7 x 10^{10} Bq, where Bq is a **Becquerel**, named after Henri Becquerel. You would expect such a close mathematical relationship because Marie Curie and Pierre Curie and Henri Becquerel all won the Nobel Prize for discovering radioactivity and sizzled and fried together. (http://en.wikipedia.org/wiki/Becquerel).

Just in the matter of temperature alone, there are oodles of people who claim fame by knowing a little something about the difference between hot and cold:

Daniel Gabriel **Fahrenheit** (F)

William John Macquorn **Rankine** (R or Ra)

William Thomson, First Baron **Kelvin** (K)

Anders **Celsius** (C)

Ole Christensen **Roemer** (Ro)

Rene Antoine Ferchault de **Reaumur** (Re)

Some of these units are no longer used and that is just as well. It all gets so confusing.

It used to be that tens of tens and hundreds of tens used to be enough. Not anymore. Besides the common minimizing prefixes of deci, centi, milli, micro, and nano, we now have pico, femto, atto, zepto, and yocto. Besides the common magnifying prefixes of deca, hecto, kilo, mega and giga, we now have tera, peta, exa, zetta, and yotta.

(http://en.wikipedia.org/wiki/Joule). You can add those to many of the measurement terms.

The International System of Units (SI) lists several name based units. Name based units are not the same thing as base units. There are only seven designated base units and of those only two were named after people. Baron Kelvin and Andre-Marie **Ampere** are the proud lenders of names for units of measure for thermodynamic temperature and electric current, respectively. (http://en.wikipedia.org/wiki/SI_base_unit) You can look up their definitions yourself.

Some other fine individuals whose names became measurements are:

- Louis Harold Gray (Gy)
- Rolf S. Sievert (Sv)
- Charles-Augustin de Coulomb (C)
- Joseph Henry (H)
- Heinrich Hertz (Hz)
- Isaac Newton (N)
- Michael Faraday (farad) (F); a picofard is also called a "puff"
- James Watt (W)
- Wilhelm Eduard Weber (Wb)
- George Ohm (omega symbol)
- James Clerk Maxwell (Mx)
- Carl-Frierich Gauss (G)
- Blaise Pascal (Pa)

Albert Einstein has the **einstein** unit named after him but the number of photons in an einstein is

(http://en.wikipedia.org/wiki/MicroEinstein) Avogadro can neener Einstein because Avogadro has his very own number. It is kind of like which professor gets the office with a window--neener neener.**Avogadro's number**.

**Pfiff **is an Austrian measurement for beer that equals one half of a **Seidel**. (http://www.unc.edu/~rowlett/units/dictP.html)

Oddly enough Avoirdupois weight is not a person whose first name is Troy and is not an apothecary.

Try that on for size.

Wikipedia was a wonderful source for much of this information. (http://en.wikipedia.org)