More on Key-stone from Infoplease:

• Key-stone - Key-stone The Key-stone State. Pennsylvania; so called from its position and importance. Source: ...
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• Tam O' Shanter - Poems and Songs of Robert Burnsby Robert Burns Verses On Captain Grose On The Birth Of A Posthumous ...
• Federal Farmer XVI - Having gone through with the organization of the government, I shall now proceed to examine more particularly those clauses which respect its powers.
• Dictionary of Phrase and Fable: K - Definitions, origins, and illustrative excerpts for words, phases, and literary allusions starting with "K"