The first stamped J. T. McNALLY INVENTOR near its weighted end; the rocking metal blade with slots for six gold denominations and three silver denominations. mounted to a wooden base; the second detector, also slotted, was patented in 1877 by Berrian Mfg.Co., N.Y. as a "Gold and Silver Counterfeit Coin Detector" and has slots for sixteen denominations.

The McNally device is 9 in. length overall

Private Collection of an Antiquarian, Charlotte, North Carolina

Both detectors in very good estate condition.