Is it 'duct' or 'duck' tape, and does it work on warts?
Actually it's both, or either.
Originally, during World War II, the US military needed strong, waterproof tape to keep water and moisture out of cases that held ammunition. Johnson & Johnson came to the rescue with what was dubbed "duck tape," with the idea being that water rolled off it "like water off a duck's back."
It wasn't long before people figured out that this "duck" tape was great for fixing all sorts of things and it became a standard item for quick repairs and generally sticking things to other things.
The original duck tape was army green, but after the war, when people found it to be useful for joining air ducts for heating and air-conditioning, a silver-colored version came out.
Nowadays "Duck" is a brand of duct tape made by Henkel Consumer Adhesives and comes in a wide range of colors and sizes. "duct" tapes are also made by all sorts of companies, so even if you have duct tape that you could refer to as "duck" tape, it may not be "Duck" brand tape.
As for using duct/duck tape to treat warts, this actually seems to work quite well and has been the subject of several serious medical studies. The idea is that you put a piece of duct tape on the wart, leave it on for about a week, and then pull it off. You have a good chance of finding the wart gone, or sort of "dead," so that you can take it off with a pumice stone.
Exactly why duct tape fixes warts is still not completely understood. One theory is that it causes local irritation, which triggers your immune system into action and gets rid of the virus that causes the warts. Sometimes warts that are not covered with duct tape will also disappear if others are treated with duct tape, so the immune boost (if that's what it is) might be systemic. There could also be a psychosomatic factor, with belief in the tape helping the body to get its act together.
Dr. Knowledge is written by physicists Stephen Reucroft and John Swain, both of Northeastern University. E-mail questions to drknowledge@globe.com or write Dr. Knowledge, c/o The Boston Globe, PO Box 55819, Boston, MA 02205-5819. 