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Show METALS SUBJECT TO STRANGE ILLS Metals, like human beings, suffer a H condition which may be termed "dls- H ease " Morbid changes, so to speak, IH occur in the pieces of metal once in a while, and frequently these condl- H tions are beyond control. Scientists jH are at a loss to explain exactly what H it is that causes a perfectly sound H appearing" piece of metal to change its IH structural strength when not under jH apparent pressure or action of either H mechanical, physical or chemical , ,'H Deficiencies in metal are often over- H come by getting a happy medium be- iH tween sufficient pressure to cause tho JH metal to flow uniformly and a pres- ll sure not so great that it will cause pl complete rupture. But these are me- H chanical changes The other changes H might be called' pathological. Tho H illness of a piece of metal often con- H tlnues progressively and ends ber- H oo H |