opposes tariff of 1816, [316];
sustains Adams, [339];
debate with Hayne, [355], [356];
his theory of the Constitution, [356];
leader of Whig party, [368];
in Tyler’s Cabinet, [372];
secures Ashburton treaty, [372];
opposes Mexican War, [379];
supports Compromise of 1850, [395];
his “Seventh of March speech,” [395];