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Assembly Multiplies Magnet Strength. — A new permanent magnet assembly, roughly three times as strong as any previously known, is a recent development of the General Electric research laboratory. It permits a tiny piece of sintered alnico to lift and hold 4,450 times its own weight. Sintered alnico is an alloy of aluminum, nickel and iron as the basic or essential ingredients, and is made by pressing together the powdered metals and heating almost to the melting point. By itself, without the special assembly, an alnico magnet has a normal lifting power of 500 times its own weight. A new mounting of brass and iron in which the magnetic flux passes through many air gaps, instead of the usual two, in bridging from pole to pole, is responsible for the greatly increased power. The new assembly is not a commercial development and the largest turned out in the laboratory to date contains but three cubic centimeters of alnico. Though smaller than a thimble, and weighing three-fourths of an ounce, this magnet in its mounting has supported as much as 200 pounds in tests.