Holger Danske (Story Time, Episode 104)

In Denmark there stands an old castle named Kronenburg, close by the Sound of Elsinore, where large ships, both English, Russian, and Prussian, pass by hundreds every day. And they salute the old castle with cannons, "Boom, boom," which is as if they said, "Good-day." And the cannons of the old castle answer "Boom," which means "Many thanks." In winter no ships sail by, for the whole Sound is covered with ice as far as the Swedish coast, and has quite the appearance of a high-road. The Danish and the Swedish flags wave, and Danes and Swedes say, "Good-day," and "Thank you" to each other, not with cannons, but with a friendly shake of the hand; and they exchange white bread and biscuits with each other, because foreign articles taste the best.