James Locke, age 13, of Charlotte, North Carolina, for his question:

How did the 21 Gun salute originate?

Formal salutes of this kind evolved with the history of warfare and its weapons. They originated to ensure the safety of visiting dignitaries. Cannon and, gun salutes, naturally came after the use of firearms. History is vague about who first thought of firing a cannon salute. But its purpose was clear. It emptied the guns of ammunition and left the scene safer for visitors. The number of shots displayed a person's rank.

Armies and navies used gun salutes before the War of Independence. In those days, 21 shots proved that all the big guns on a ship were safely empty. This salute was and still is, reserved for presidents, visiting royalty and heads of state. Our flag also gets the 21 gun salute. But on July 4th, 50 guns are fired to salute the 50 states. Vice Presidents get 19 salutes, generals get 18. Vice consuls get the five gun salute.