①What did people do to communicate in ancient times? Here are some very interesting answer s to this question.
②Alphorns(阿尔卑斯长号角) were once used to communicate in the mountains in Switzerland. They are very long and they are very heavy, too. So, alpharns are hard work to blow. Then why use them? Well,they make a loud sound which travels much further than the human voice. Herdsmen(牧民) used them to call cows in the distance for milking. At sunset, alpharns were also used to send a message down to villagers that all was well. These days, they're mostly used as musical instruments.
③The people ofLa Gomera, an island in Europe, have their own special way of sending messages from mountain to mountain. They use a whistled(口哨的) language called el silbo, which comes from their language . Spanish. Whistling can be heard within five kilometers, which means it can be used across much greater distances than shouting. El silbo can be used for all kinds of messages, including greetings and announcements. El si lbo is used a lot less than it used to be, but primary school students in La Gomera have to leave it.
④Did you know it's also possible to send messages without making a noise? This is called visual communication, and it includes the use of flags and even smoke. Long ago, soldiers along the Great Wall of China used smoke as a warning. If they noticed the enemy from their signal(信号) tower, they li t a smoky fire. When soldiers in other towers saw the smoke signal, they lit fires too. In this way, messages about the enemy's arrival could travel as far as 800 km in just a few hours.
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