Superconductivity and carbon nanotubes, are Type I, while almost all impure and compound superconductors are Type II. Conversely, a spinning superconductor generates a magnetic field, precisely aligned with the spin axis. The effect, the London moment, was put to good use in Gravity Probe B. This experiment measured the magnetic fields of four superconducting gyroscopes to determine their spin axes. This was critical to the experiment since it is one of the few ways to accurately determine the spin axis of an otherwise featureless sphere. Superconductivity was discovered on April 8, 1911 by Heike Kamerlingh Onnes, who was studying the resistance
What Katy Did School (set in Hanover, New Hampshire); "What Katy Did Next", in which a new friend of Katy's takes her on a once-in-a-lifetime trip to Europe; "Clover", in which Katy is married and Clover accompanies her brother Phil to Colorado after he falls ill; and "In the High Valley", which shows the lives of a handful of young people living in the High Valley in Colorado, including Clover, Elsie and their husbands. What Katy Did What Katy Did is an 1872 children's book written by Sarah Chauncey Woolsey under her pen name Susan Coolidge. It follows the adventures of a twelve-year-old