1. On December 18, 1787, New Jersey became the third state to ratify the United States Constitution. The state played a crucial role in the formation of the federal government and its decision to ratify the Constitution helped set the stage for a strong federal system.

2. In 1831, the first iron-hulled steamboat, the John Stevens, was launched in Hoboken, New Jersey. Named after its inventor, the John Stevens revolutionized the shipping industry and helped pave the way for the modern steamship.

3. On December 18, 1865, the 13th Amendment to the United States Constitution was ratified, officially abolishing slavery and involuntary servitude in the country. New Jersey was among the states that supported the amendment and played a crucial role in the fight against slavery.

4. In 1915, the first self-service grocery store, Piggly Wiggly, opened in Trenton, New Jersey. The concept allowed customers to select their own items from shelves rather than rely on a store clerk, and it quickly became popular across the country.

5. On December 18, 1940, the building that would eventually become the New Jersey State Museum was dedicated in Trenton. The museum has since become a significant cultural institution, featuring collections related to archaeology, fine art, natural history, and more.