The oldest known door lock was found in the ruins of the Egyptian palace known as Khorsabad, located in the country now known as Iraq. This door lock is estimated to be roughly 4,000 years old. Incredibly, it was constructed entirely out of wood. Even more incredibly, the lock was operated by more or less the same mechanics as today's pin tumbler locks.
These locks utilized a wooden bar located within a hollowed out portion of the door itself. When slid across into a corresponding hole in the door frame, the bar would prevent the door from being opened. A rudimentary wooden key was inserted into a hole on the front of the door to unlock it. This wooden key had teeth just like today's locks.
The teeth of the wooden key would push up on special pins that acted to hold the wooden bar in place. With these pins lifted, the bar could then slide back, and the door opened. This likely took quite a bit of strength since the bars in question were up to 2 feet long and made from solid wood.
The Romans tend to be credited with the development of the first metal locks. These followed the same tumbler design as Egyptian wooden locks — although they tended to be somewhat smaller. Locks were used on chests to contain items of great value. To own a key was seen as a sign of great status since it meant that you had objects worthy of protection.
For this reason, many Romans turned their keys into articles of jewelry. They often wore them around the neck on chains of precious metal. Others would have circular portions added to the base of their keys, allowing them to wear them like rings. These keys also often contained decorative elements that reflected the places where the locks were.
The tumbler locks constructed by the Ancient Egyptians contained multiple pins, each of which had to be lifted upward in order to move the bolt. Yet the distance that you had to lift these pins didn't really matter. They simply had to go high enough to disengage from the slots of a plate at the bottom of the lock.
For hundreds of years — and perhaps thousands — locks continued to operate according to this same basic premise. Yet such locks were flawed in that someone could pick them with relative ease. All a would-be thief had to do was raise all of the internal pins. A new type of lock invented by Robert Barron in 1778 made things much harder.
This new type of lock featured what is known as a double-acting lever tumbler. Inside of the lock were four different levers. These levers differed from those in older locks in that two of them had to be lifted to different heights. This made the task of picking the lot much more difficult.
Locks and keys have a long and colorful history in human societies and have never been more important than they are today. For assistance with all of your lock needs, please don't hesitate to call our security experts at Vista Lock & Safe Co.