Magnets are fascinating. Imagine the amazement of the ancient Greeks who discovered that some naturally occurring stones, later named magnetite because they were found in the region of Magnesia, attracted iron. The stones also quickly attracted superstitious beliefs. Magnetite was said to have the ability to heal the sick and frighten away evil spirits. Archimedes is said to have used magnetite to remove nails from enemy ships and sink them. Magnets never sank ships but were used to guide them. We are talking about the compass. 

Thousands of years ago the Chinese also noted the properties of naturally occurring magnetite. When made into the shape of a needle and floated on water, the magnetite always lined up in a north-south direction. By about 1000 AD, the Chinese had developed the compass that became the key to navigation. But magnets have also been used to navigate people away from reality.  

During the 18th century, James Graham briefly studied medicine in Edinburgh then travelled to Philadelphia where he became acquainted with Benjamin Franklin’s experiments with electricity and magnetism. Could this mysterious force of magnetism be applied to the field of medicine, Graham wondered? His crafty mind began to formulate an idea. If doctors could claim to cure illness by blood letting, cupping or foul purgatives and emetics, why not add magnets to the list? And so the idea for a Temple of Health was born. 

This impressive establishment, which opened in 1780, housed a lecture room where Graham delivered unsubstantiated lectures on magnetic healing. There was also number of chambers equipped with paraphernalia that supposedly delivered the goods. Patients could choose between a magnetic throne or an electrical bath. The central attraction, however, was the Celestial, or electro-magnetic, bed. For £100 a night, childless couples could rent the elaborately decorated bed and frolic amorously while exposed to the effects of 1,700 pounds of magnets built into the frame. Conception was guaranteed. 

For a while, the Temple was the place for the fashionable. But its popularity waned and Graham’s ego suffered. He took to doping himself with ether vapour and running through the streets, sometimes even stripping off his clothes to help a beggar. Graham died insane at age 49.
Magnets are great placebos. Today, magnetized bracelets can be purchased to energize the gullible. And you can buy magnetic laundry disks for insertion into washing machines to clean clothes without using detergents. The claim is that the magnets ionize water and thereby increase its cleaning ability, which of course is nonsense.  

Advertisements for these products often attack commercial detergents, accusing them of containing cancer-causing chemicals and hormone disruptors. The claim is that the magnetic disks reduce health risks by eliminating exposure to these substances while also saving money, since there is no need to purchase detergent. References are given to a patent for the laundry disks, as well as to a study supposedly demonstrating their cleaning efficacy.  

It is important to understand that the only requirement for obtaining a patent is novelty. When it comes to the patent, there is no need to show that the magnets actually do anything, just that their use in this context is novel. How about the study carried out by a testing lab that examined the cleaning efficacy? Technicians took bundles of clothes, washed them in a magnet-equipped washing machine and demonstrated they came out cleaner than they went in. Surprise! Water is an excellent solvent and cleans remarkably well even without any detergent. 

Is there any rationale that magnets can actually do something? Water is diamagnetic, which means that it will be repelled by a magnet. But the effect is very, very small. If a vial of water is placed on a piece of floating foamed polystyrene and a strong magnet is brought close, it will slowly move away from the magnet. It’s an interesting phenomenon but has nothing to do with cleaning ability. However, there is something about the advertising for the laundry disks that is not contestable. They are guaranteed to last for 50 years, a claim that is indeed safe since magnets do not rot. This is more than what can be said about their miraculous cleaning properties.   

Joe Schwarcz is the director of McGill­ University­’s Office for Science and Society. Read his blog at