Does anyone know the history of chain saws? Newspapers need it!

At first, people used axes to cut wood, which was cumbersome, time-consuming and laborious. During the Warring States Period in China, Lu Ban invented the world's first saw blade based on the fine teeth of silk grass leaves, and people began to use it to cut trees, which greatly improved the logging efficiency. In the United States in the19th century, innovative logging tools developed with chains appeared. The first one is Moore in California. The lumberjack he invented was a bit huge and needed to be hoisted by a crane to work, so it was inconvenient to operate and did not circulate in the market. The other is that Hamilton invented a rotary saw in 1880, which was also eliminated by the market because it was bulky and impractical; Decades later, Andre Steele, a German, invented the world's first chainsaw, which was a milestone. This chainsaw is actually a chainsaw, weighing 63kg, and then he invented the gasoline engine chainsaw in 1929. At the same time, Emile Lepp, another German, also developed a gasoline chain saw and founded DOLMAR Company in Hamburg. At this time, the chain saw engine was inefficient and huge, requiring two people to carry the work, and even some chain saws needed to be transported to the Woods by car. Although World War II brought a gunpowder war to the world, it also triggered a technological revolution. The invention of aluminum alloy greatly improved the mechanical properties. This material is light in weight, easy to process and high in strength. At the same time, it promoted the development of chain saw, greatly improved the efficiency of engine, invented two-stroke engine and accelerated the development of chain saw. An American named Cox has made outstanding contributions to the development of chain saws. He is very dissatisfied with the inefficient work of the chainsaw and the need to polish the blade every time he uses it. Cox once happened to see that beetle larvae could chew very hard wood. Careful observation that the larvae' mouths are C-shaped narrow mouths may be the secret of their ability to chew wood. Cox invented the C-type cutting blade through repeated experiments, and established Oregon Chain Company in 1947, which achieved great success. This is the world's first "chipping" chain. At the same time, ROBERT MCCULLOUFH FH established mccullough FH Automobile Company in 1943, specializing in the production of small gasoline engines. 1948, he introduced his first chain saw model 5-49CS. 1950, Steele introduced the real one-man chain saw. Until 1970 and the rise of Japan in 1980s and China in 2000, Germany and the United States occupied the market for many years. Notable signs are the launch of 1959 STIHLS CONTRA light chain saw and the launch of 1963 Li Kang XL 12 model. This chain saw adopts the first Oregon 72D chain saw with a groove width of 3/8 ",which is still used today. In Australia, ATOM Industry applied for their chain saw starting system patent at 1972; At the same time, it also applied for the patent of "turbo charging, automatic air filter". They also invented the anti-tooth drill fittings, which can drill holes in fences and wires. The invention is widely used in the field of professional machinery. Anti-vibration system, quick braking and other safety equipment have further reduced the weight of chain saws and better balanced them, which have been widely used in modern chain saws. Chain saws use ice crystal blades, hydraulic transmission and water cooling technology. Now they are not only used in logging market, but also widely used in cutting stones, bricks, building concrete and rescue equipment, and even artistic carving.