The roar of a chain saw is a sound that is hard to separate from images of destruction and violence. Horror movies and wildlife documentaries have taught us that chain saws are, in general, a "bad thing." For maintenance workers and lumberjacks in the 1920s,the invention of the chain saw was undoubtedly a blessing.
It is possible that early chain saws were in use before World War I, although there is little solid evidence for this and it was not until World War II that Andreas StihI's (1896-1973) "hand held mobile chain saw," invented in 1927, came into its own. German troops used the saws for making quick progress through wooded areas. When the Allies caught wind of this, they promptly dropped a bomb on the Germans' chain saw factory—but not before stealing a saw for themselves so that they could copy it.
StihI's original chain saw was equal in weight to an average teenage boy and required two people to wield it. Having studied the stolen German chain saw, a U.S. company called Mercury developed an improved version that could be held by a single person. StihI's company fought back and, by the 1970s, claimed to be the world's largest manufacturer of the machines.
In recent decades, chain saws have helped to bring about the destruction of some of the most diverse areas of life on Earth. The BBC series "Life of Birds" famously, and tragically, shows the lyre bird mimicking the sounds of chain saws destroying its natural habitat. As chain saws rip through the Amazonian rain forest— not to mention practically every other tree-studded landscape on the planet—it is hard to find sympathy with the loggers.
