■ On Sept. 17, 1787, the Constitution of the United States is signed by 38 of 41 delegates present at the Constitutional Convention in Philadelphia. It would not become binding until it was ratified by nine of the 13 states. Nine months later, New Hampshire became the ninth state to ratify the document. ■ On Sept. 18, 1793, George Washington lays the cornerstone to the United States Capitol building. It would take nearly a century to complete, as architects came and went, the British set fire to it and it was called into use during the Civil War. ■ On Sept. 16,