Change of key and lock
When the primitive people lived in the cave, for safety, sometimes to promote the boulder to block the hole, it is not prepared to prevent the thief but the beast. After the emergence of private ownership, the thief appeared, so the lock was born.
Far more than three thousand years ago, China has a lock. However, the earliest lock no organs, but made of tigers and other ferocious animal shape, would like to scare the thief, can only be said to be a symbolic lock.
It is said that Luban is the first to lock the organs of the people. From the unearthed cultural relics and written records reflected in the situation, the ancient lock is by two plate spring elastic work. Until now, this spring is still in use.
In foreign countries, although the ancient Greeks have found a very reliable lock, but the key is larger, to carry on the shoulders, it is difficult to universal in the general family. Ancient Indians made another bird-shaped "fan lock", the keyhole hidden in the wings can be withered. The rise of modern lock first by the 18th century British invented the "welding fishing lock". We are now widely used in the ball lock, is the United States small Nerus Yale invented in 1860.
And the invention of the key than the lock later ancient Egyptian is the world's first use of the key. Their lock is a wooden door bolt into a slot, the top of the groove there is a wooden bolt. When the plug is inserted into the groove, the wooden plug will be inserted into the hole of the bolt. In this way, the bolt will be very strong, you must use the key to open.
As the Egyptian lock can only be used in the side of the door bolt, is not conducive to the flexibility to open and close, so the Greeks on this basis, but also developed a lock from the other side of the lock. The keys made by the Greeks were a curved stick, shaped like a small sickle with a farmer. But there are some keys up to 3 feet, must be carried on the shoulders to move, quite heavy.
The Romans can be said to be the most sophisticated locksmith of ancient times, and they have considerable research on the standard of making keys, and have learned that the nails at the end of the key are cut into various shapes.