Reading UNIT 4

What is the 'Polybius Square'?

• A form of ancient cryptography

• A complex system of alphabetical signals

• A type of smoke signal

• A method of written communication

How did soldiers on the Great Wall of China use smoke signals?

• To signal the end of the day

• To celebrate victories

• To warn about approaching danger

• To communicate with nearby villages

Who invented the complex system of alphabetical smoke signals?

• Aborigines of Australia

• Greek historians

• Ancient Chinese soldiers

• Polybius

What did the position of the smoke on a hill indicate for the Native Americans?

• The need for help

• The presence of danger

• The arrival of new people

• The time of day

How do the American Boy Scouts use smoke signals on camping trips?

• To indicate the end of the day

• To signal the start of a race

• To invite others for a meal

• To indicate someone is in danger

What do people use to send smoke signals at sea to ask for help?

• A mirror

• A whistle

• A special object called a flare

• A torch

What is the purpose of smoke signals in the Vatican?

• To indicate the selection of a new Pope

• To signal the end of a meeting

• To communicate with nearby churches

• To celebrate religious festivals

How far could the Ancient Chinese soldiers transmit a message using smoke signals?

• 500 kilometers

• 1000 kilometers

• 1500 kilometers

• 750 kilometers

What did the Aborigines of Australia use smoke signals for?

• To invite others for a meal

• To communicate with other tribes

• To indicate the presence of danger

• To signal the end of a journey

What is the main purpose of smoke signals in general?

• To communicate news

• To signal danger

• To invite people to a certain place

• All of the above