The Blaisdell Blog

  On the night of February 21, 1944, a Norwegian named Knut (please pronounce the “K”—it is not a silent letter) Haukelid and two of his friends approached the Ferry Hydro docked on the shore of Lake Tinnsjå in Telemark, Norway.   Tinnsjå is one of the largest and deepest lakes in Europe.   Knut and his recruits needed the deepest lake in Norway, because they needed to sink the Hydro in the deepest water they could find.   These men, working late in the night, planted over eight kilograms of plastic explosives in the boats keel, and armed it with two hand wound alarm clocks.   Shortly after midnight, just as the Hydro moved over the deepest water in Lake Tinnsjå, an explosion tore through the hull and sunk the boat, sending its cargo the bottom.   Knut Haukelid watched the ship go down with tears in his eyes.   There had been Norwegian nationals on that boat; and he could not warn even one of them.   Because there was also a shipment of heavy water on the Hydro .   Heavy water i

  On October 25, 1415, Henry V of England laid some serious hurt on the French at the Battle of Agincourt at Pas-de-Calais, France.   Part of the success of this campaign was due to Henry’s use of the longbow, but part of it also goes to the creative use of military indentures.   These legal contracts required all the English captains to provide specified amounts of men, material and time to the King’s cause.             An indenture was a document, written in duplicate and then torn along a jagged line, like little teeth ( dents ), in the paper.   One portion of the contract was in possession of each party and when the required conditions and period of service were fulfilled, the parts reunited, and the debt was considered paid.   Many of the people who first came to this country from England came as indentured servants, worked off their debt and became the backbone of the country.             Today we are creating a nation not of indentured servants, someone with a carefully

  Katie Mack’s article in the Washington Post this Sunday focused on her reaction to the news that gravitational waves have been found to constantly writhe and contort their way through the universe.   That put me in mind of this article that I originally wrote for the Mensa Bulletin and later made its way into the MIT physics newsletter.   The music of the spheres is, indeed, a joyful noise.   Has your eye ever been captured by the beauty of a pearl, the milky sheen with just a hint—almost imagined—of blush?     That blush makes pearls seem to be living things.   When I first learned what a pearl was and how it was made, I thought it was a grand mystery.   The thought of something so pure and perfect starting with an irritating grain of sand, growing with the sticky mucus of an ugly bivalve seemed to be miraculous to the point of supernatural.   Pearls became my fairyland of choice.     On rainy days, when Minnesota skies was filled with gray and drear, I would steal away to