Thanks goodness for Napoleon for pushing through a common measurement.

+Joel Reid   Interestingly, it turns out that Napolean actually worked against the metric system when he issued a counter-decree (1812) that permitted the ordinary measures to continue to be used in France.  That had to be repealed 25 years later by edicts from the regime of King Louis-Philippe (1837; 1840) which re-established the metric system as universal and compulsory throughout France.

The dawn of the metric system has a fascinating history.  It actually took off in 1790, when King Louis XVI sanctioned the initial recommendation by the French Academy of Sciences to pursue a universal measurement system. 

But that was already a year into the unrest that would eventually become the French Revolution and lead to Louis XVI's departure from the throne (1791).

Meanwhile, the governing committee of the Academy of Sciences that was overseeing the development of this new universal measurement system was comprised of five heavy-weights of French mathematics: Borda, Lagrange, Laplace, Monge, and Condorcet.  Their work was inherited by the revolutionary government that succeeded Louis XVI, and practical surveying was begun.

It was the revolutionary government that hurriedly adopted the first universal system of measures, decreeing in 1795 the use of a "provisional meter" even whilst the calculations for an absolute "terrestrial meter" were still underway.

The terrestrial standards were finally completed and adopted on 10 December, 1799 as the definitive standard for length through the Republic.

While Napolean's conquests and Civil Codes certainly helped spread the use of the metric system throughout the French Empire, he cannot (IMO) be given credit for specifically advancing its adoption due to his retrograde decree (see the previous comment).

So interestingly, one might say that it was two kings and a number of mathematicians  and an intervening revolution that delivered the universal system of measures from which our modern systems trace their origin!

So thank goodness for Louis then :)

+Assad Ebrahim very nice post! Thanks!

Spare the rod and spoil the child.

so they were pretty clever in the medieval time after all. that's a fantastic way to work out a standard like that.

+Mark Webster  Yes, quite clever that way of introducing random sampling.

Especially since at the time almost the whole population visited church. Makes random sampling a bit easier.

Great post - I teach a section on standard units of measure in oceanography at Miami Dade College. I think I'll start out that section next semester by picking 16 students...

+Erik Stabenau   Nice!  To carry over the analogy for oceanography, suppose each of the sixteen men also draw at random a power from the collection 10^-4, 10^-7, ..., 10^0, ..., 10^+4.  Each man's foot is scaled accordingly, i.e. is randomly between a thousandth the size or a thousand times the size.

What standard unit of measure would permit working readily with this wide dynamic range of measurements? 

The decibel, which is the practical man's logarithms, and appears everywhere in oceanography.

There's a great quote by Laplace, whose tribute to the logarithm was much more glowing than the typical student reaction: 
"[Logarithms: that] admirable artifice which, by reducing to a few days the labour of many months, doubles the life of the astronomer, and spares him the errors and disgust inseparable from long calculations."

Substitute oceanographer for astronomer and the sentiment, I think, remains the same.