Originally Posted by Writerhall
I read a mystery novel once where the captured woman surreptitiously dug out the wire in her underwire bra to stab the bad guy with.
Be careful when wearing an underwire bra because it can actually throw off the compass.
I was on an archaeological project and we were mapping with a Brunton compass on a tripod. To read the compass you had to lean over the compass to look straight down on it. One girl on the project could never get the same reading as everyone else. We finally figured out the underwire in her bra was magnetic and throwing off the compass!
While I'm dishing out public service announcements, I was on another project and showing an archaeologist how to use a sighting compass. She couldn't get the proper reading either. It turned out that the piercing in her eyebrow was magnetic and throwing off the sighting compass.