An instrument for regulating or adjusting a circuit so that any required degree of resistance may be maintained.
William Dwight Whitney The Century Dictionary and Cyclopedia: An encyclopedic Lexicon of the English Language (New York, NY: The Century Co., 1889)
2400×1160, 363.4 KiB
1024×494, 62.2 KiB
640×309, 33.7 KiB
320×154, 12.9 KiB