Congress passes the Tariff Act of 1833, sometimes called the Compromise Tariff, proposed by Henry Clay and calling for the gradual reduction of tariffs to the 1816 levels, ending the Nullification Crisis
The U. S. Congress passes a proposed 13th Amendment stating that the Congress will not abolish or interfer with slavery where it exists. The amendment is never ratified.
Congress rejects a call by President Lincoln to adopt a standard railroad gauge of 5 feet and adopts the 4 foot, 8 and one-half inches gauge. It is sometimes called the Congressional gauge.
After withdrawing from New Madrid Confederates control Island No. 10, blocking shipping on the Mississippi. Over 5,000 Confederate soldiers on the island surrender to Major General John Pope on April 8.