The Guardian's Thursday science section is a very worthwhile purchase. Some 20 pages with generally thoroughly researched content as well as a humourous column called "Bad Science". Sometimes, though, as a physicist, it's easy to be too quick to generalize when observing general phenomena.
Snippet from Ben Goldacre's Bad Science section Thursday May 27th this year:
David Bradbury sends us in The Eye Zone Massager, another classic piece of pseudoscience from those folks at the Science Museum gift shop. "At the end of a stressful day, use this special mask for a few minutes. It massages the temples and eye area, reducing stress and energising muscles. Very refreshing, it helps prevent bags and dark rings. Gentle magnets also enhance circulation. Battery included." No. Again, no. Gentle magnets do not enhance circulation. Blood is not magnetic: and why not try these fun demonstrations at home to prove it. Bleed yourself on to a dish and wave a magnet over it: observe your blood not moving. Hold a magnet over your skin, and watch it not go red. Put yourself in an MRI scanner with a massive magnetic field, and carefully note that you are not hovering, in a dramatic living demonstration of the non-magneticness of your blood. Get a job on a scrapyard, hang out under that big electromagnet they use to pick up the cars, and notice that you do not fly up into the sky, and do not smash your skull into lots of tiny pieces. Regardless of what the Science Museum's merchandise tells you, kids, blood is not magnetic. Unless, of course, the shop is aware of this and an interactive demonstration of the more cynical commercial applications of science.A great piece of debunking those magnetic armbands / shoe soles / etc sold everywhere for gullible takers. ... until Mark van Ments wrote a letter to the editor:
Although blood does not appear to be magnetic at common levels of magnetism, I believe you are wrong to say it is not affected by magnetism at all (Bad Science, May 27). With a sufficient magnetic field it is possible to levitate any material, including blood, or even an entire frog using magnetism.Photos of a hovering frog(!) here. Corrections and clarification of the difference between ferro-magnetism and diamagnetism from the Guardian here.
As to the medical benefits of using magnetism in this way, apparently the frog suffered no ill effects.
Buy the Thursday Guardians... Or at least stop by their Bad Science section from time to time for a good, well-researched and cleverly written laugh...
Anders Jacobsen |