1998: The New York Stock Exchange implements its "circuit-breaker" rules, mandating trading halts when the market drops at least 10%.

1955: A middle-aged milkshake-mixer salesman named Ray Kroc opens the first McDonald's franchise in Des Plaines, Ill. It racks up $366.12 in sales of 15-cent hamburgers and 10-cent french fries on the first day.

1954: Under a new provision of the U.S. Internal Revenue Code, April 15th becomes the due date for individual tax returns.

1926: Charles A. Lindbergh makes one of the earliest commercial air flights, zipping between Chicago and St. Louis in a deHaviland DH-4 biplane to deliver a sack of mail for Robertson Aircraft Corp., under contract from the U.S. Post Office. Robertson later grows into American Airlines.

1912: Early in the morning, after striking an iceberg around midnight, the Titanic sinks to the bottom of the North Atlantic. Making a cold calculation about the uninsured value of the vessel, and counting the 1,500 fatalities at zero, the stock market crunches $2.6 million off the total capitalization of International Mercantile Marine Co., the owner of the doomed oceanliner.

Arun Khanna, "The Titanic: the Untold Economic Story," Financial Analysts Journal, September/October 1998, pp. 16-17