hicago, Il. A which presses against the blade when inserted, the At a recent meeting of the Royal Microscopical 8o- blade being quickly adjusted in correct position by diamond-shaped base plate of insulating material has ciety, Dr. J. E. Talmage, of Salt Lake City, Utah, ex- on its opposite sides… … headed face cards that have absolutely the same aspect in both directions, the small figure, the center of each plate having an The following is the manner in which the opening for a screw, and these screws being con- operator can recognize the card inverted. ductors. A third screw at one end is…
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