Sept 17, 1787. Delegations from 12 states (Rhode Island did not send a delegate) at the Constitutional Convention at Philadelphia, PA, voted unanimously to approve the proposed document. Thirty-nine of the 42 delegates present signed it, and the Convention adjourned, after drafting a letter of transmittal to the Congress. The proposed constitution stipulated that it would take effect when ratified by nine states. Read more at http://www.archives.gov/education/lessons/constitution-day/.
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