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No. 3292:
An Old Ruler

     Today, an old ruler. The University of Houston presents this series about the machines that make our civilization run, and the people whose ingenuity created them. 

     We’ve all watched Saturday Night Live for years.  It’s mostly political satire.  But they recently did something quite different: Here General George Washington speaks to his troops.  They’re fighting for our future and our freedom to choose.  So, he tells of a dream he’s had.

     His dream was of that future – one where we’re free to choose our own system of weights and measures.  Those regimented French, he says ... They use centimeters, meters, and kilometers.  They’re all bound by factors of ten.  Well, we’ll have a much freer system!  We’ll multiply inches by twelve, to get a foot.  We’ll multiply feet by five thousand, two hundred, and eighty, to get a mile.

     He goes on: He lays waste to our dimensional isolationism.  He tears into units of weight, volume, temperature.  It all makes fine comedy.  Well ... let me offer my own strange story of how that actually did play out in one American industry.

    The year is now 1951: My first engineering job is at Boeing.  I’m designing parts for their new B-52A bomber.  I use my own drafting instruments as I work at a huge drawing board.  But the company provides me with a special ruler.


    Now, think what rulers look like: Twelve inches, all divided into quarters, eighths, and sixteenths of an inch.  Well, this is different: Its inches are divided into tenths.  And each tenth is subdivided into tiny slices, two one-hundredths of an inch wide.  You see, Boeing conceived the airplane itself in one-inch sections.  The B-52’s body was – is – one thousand, nine hundred, and twelve inches long.

    Boeing had created its own decimal system within the company.  Just think how much labor they cut when we didn’t have to keep multiplying and dividing by 12!  How much more time did we save when we didn’t have fractions like three-eighths of an inch

    That was 72 years ago, as I write.  Today, not only has the world abandoned our English system of units.  We’ve also abandoned the old French metric system in favor of the International System of units.  We commonly call that SI for Systeme International.  At first glance, SI seems to use many old metric units.  But it’s shot through with improvements.


    Officially, the US uses SI units.  Take our inch: We define it as 2.54 centimeters.  Our large industries have to use SI units as they deal with worldwide markets.  But we Americans keep resisting.  We cling to our dimensional isolationism.

    Meanwhile, I keep my fine durable old white plastic Boeing ruler.  It once represented a halfway escape from a clumsy system that’s doomed in any efficient industry.  And I still use that ruler, all the time.  It’s so much more convenient than one marked in sixteenths of an inch.  Of course – and here is the kicker – It’s still twelve, not ten, inches long.

    I’m John Lienhard, at the University of Houston, where we’re interested in the way inventive minds work. 

(Theme Music)


Here is a link to the SNL skit that I mention:

You will find the International System of Units (or SI) (which is now the official system for the United States) described in detail here:

Here is the history of the B52:  

I worked on the B52A.  The current model is the B52H.  Wikipedia gives its length as 159 ft. 4 in, or 1912 inches.  I’m guessing that it was the same for the B52A.  The original experimental B52Y and the B52A both replaced the conventional electrical system (used to power auxiliary power needs) with a pneumatic system.  The B52Y’s system exploded in a pressure test while we worked on the B52A.  In the end, Boeing built only three B52As.  Then they reverted to a conventional electric system.

I attribute certain words to General Washington in the SNL skit.  He did not actually speak those words.  Rather, they were the gist of his message.

Also, I should note that, in the past, any ruler with units on it, was called a scale, not a ruler.

Thanks to Pat Cook for drawing my attention to the SNL skit.

This episode first aired on 11/17/2023