of
silicon. Similar products are known as "duriron" and "Buflokast" in
America, "metilure" in France, "ileanite" in Italy and "neutraleisen" in
Germany. It is a silvery-white close-grained iron, very hard and rather
brittle, somewhat like cast iron but with silicon as the main additional
ingredient in place of carbon. It is difficult to cut or drill but may
be ground into shape by the new abrasives. It is rustproof and is not
attacked by sulfuric, nitric or acetic acid, hot or cold, diluted or
concentrated. It does not resist so well hydrochloric acid or sulfur
dioxide or alkalies.
The value of iron lies in its versatility. It is a dozen metals in one.
It can be made hard or soft, brittle or malleable, tough or weak,
resistant or flexible, elastic or pliant, magnetic or non-magnetic, more
or less conductive to electricity, by slight changes of composition or
mere differences of treatment. No wonder that the medieval mind ascribed
these mysterious transformations to witchcraft. But the modern
micrometallurgist, by etching the surface of steel and photographing it,
shows it up as composite as a block of granite.
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