How Long is a Day? How Heavy is a Kilogram? - In Praise of Metrology

Every once in a while I notice a story about metrology, or the science of measurement, that reminds me how many of our concepts about the world are carefully constructed and contingent. A few months ago I asked just how long ago the civil war was after hearing a story about a book stolen during the civil war and just recently returned. On the scale of a human life or generation the civil war is very recent history and yet America seems to have completely buried it in the past.

Just How Long Ago Was the Civil War?

I heard a story on All Things Considered this afternoon about a book that was returned to Washington and Lee University in Virginia, 145 years after it was stolen. Let’s see 2009-145 = 1864. That’s nearing the end of the American Civil War. The Battle of Gettysburg took place July 1-3 of 1863. The South surrendered at Appomattox on April 9, 1865. Washington and Lee University is located in Lexington, VA near the western border of Virginia.