On May 25, 1787, the fifty-five delegates to the Constitutional Convention began meeting in a room, no bigger than a large schoolroom, in Philadelphia’s State House. They posted sentries at the doors and windows to keep their “secrets from flying out.” They barred the press and public, and took a vow not to reveal to anyone the words spoken there. There were speeches of two, three, and four hours. The convention, which lasted four months, took only a single eleven-day break.

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