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• The period in which the American Upper Silurian system, containing the brine-producing rocks of central New York, was formed. See the Chart of Geology.

2010 - New Age Dictionary Database
By Oddity Software

• The period in which the American Upper Silurian system, containing the brine-producing rocks of central New York, was formed. See the Chart of Geology.

1913 - Webster's Revised Unabridged Dictionary
By Noah Webster.