Word Study
nobili's rings
CIDE DICTIONARY
nobili's rings, [After Leopoldo Nobili , an Italian physicist who first described them in 1826.].
Colored rings formed upon a metal plate by the electrolytic disposition of copper, lead peroxide, etc. They may be produced by touching with a pointed zinc rod a silver plate on which is a solution of copper sulphate. [Webster 1913 Suppl.]
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