Being the oldest and most effective original telegram, beacon towers are
the most important component of the defensive project on the Great
Wall. They are built continually to pass military messages. In ancient
times, if intruders approached, soldiers on the wall would create smoke
in the daytime and light a fire at night to warn their troops.
Silent Spring is a book that talked about how the pesticides make a detrimental effect on the environment, especially on birds. The chemical industry was accused by Carson of spreading disinformation.
