Researches on diamagnetism and magne-crystallic action : including the question of diamagnetic polarity (1870)
Tyndall, John, 1820-1893 · London : Longmans, Green · leaf 160
long, 5^inches external and 2 inches internal diameter. The wirecomposing them is one-tenth of an inch thick, and so coiledthat the current could be sent through four wires simultaneously.Within these helices were introduced two cores of soft iron 2inches thick and 14 inches long : the ends of the…
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