History of the Metal Detector
Metal detectors are instruments that use electromagnetic induction to detect metal. Metal detectors have existed for decades and have been known to have a variety of benefits in terms of detecting weapons as well as treasure hunting. Archaeologists, security officers, treasure hunters, construction officers and even food technologists have found a lot of use for this kind of technology and have taken advantage of its benefits over the years.
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Initial Development
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Alexander Graham Bell invented and used the first metal detector in 1881 when President James Garfield lay dying from a bullet fired by an assassin. To respond to this crisis, Bell hurriedly assembled a makeshift metal detector to detect the bullet and save the President's life. However, he did not succeed in finding the metal. Nevertheless, on the next day, it was found that the metal coils the President was laying on confused the metal detector, resulting in mechanical failure.
First Patent Application
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Banking on Bell's discovery, in 1925, Gerhard Fisher applied for and received a patent for the first metal detector. Fisher made improvements on Bell's initial development and used it for aircraft radio direction finders. Back then, Fisher was a research engineer in Los Angeles, California, and also graduated from the University of Dresden in electronics studies.
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Fisher Spawns Large-Scale Production
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Fisher's invention of the metal detector came about somewhat by accident. An aircraft malfunction that causes errors in the bearings when metallic objects come between the transmitter and receiver or if the bearings pass over areas with minerals aided Fisher's discovery. Fisher investigated this occurrence and found out that the malfunction was the effect of mineralized areas. Fisher later developed the metal detector which is used to detect small buried objects and ore deposits. Fisher's metal detector was sold commercially in 1931. Fisher Research Laboratory, founded by Gerhard Fisher, was behind the large-scale production of metal detectors.
Further Developments
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The modern metal detector is not Fisher's version. Over the years, people have been developing the technology, as metal detectors have been used for treasure hunting and other various purposes. During World War II, there came a need for land mine detectors. In turn, the government instructed manufacturers to conduct more research for this technology to be used effectively. During the war, a large number of these units were bought.
When the war finally came to an end, the surplus manufactured was sold to the public and was used to hunt for buried gold and silver.
After the War
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During the 1980s, the metal detector's accuracy was developed along with its ability to identify types of metals detected by its transmitting field. As time went by, the size of the metal detector shrunk considerably, making them even more user-friendly and portable.
Modern metal detectors now have the ability to pinpoint their targets, measure the depth of the metal's location, and even inform the user on the nature of the metal. Further developments have been made to make the technology more sophisticated, thus increasing its possibilities of application.
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