What is a substance resembling gun cotton in composition and properties, but distinct in that it is more highly nitrified and is soluble in alcohol, ether, etc.; -- called also pyroxyle called?

pyroxylin — A substance resembling gun cotton in composition and properties, but distinct in that it is more highly nitrified and is soluble in alcohol, ether, etc.; -- called also pyroxyle. (Webster's 1913.)

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