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
Harm Kamerlingh Onnes the physicist and Nobel Prize winner Heike Kamerlingh Onnes. In his early years from 1915 to 1925 his work was influenced by modernism. In 1918 he designed a number of abstract stained-glass windows for the Spark House, which was designed by Jacobus Oud. From 1925, he started to take the everyday reality as his subject, and from that time he only made figurative works. It was after a visit to the studio of Mondrian, that he had realized that abstract art was not for him. Some of his designs for stained-glass windows have discoveries of physicists Pieter Zeeman and Hendrik