# What is a Witching Signal? **URL:** \ **Category:** Factual Questions\ **Created:** [May 8, 2025, 7:40pm UTC](https://boards.straightdope.com/t/what-is-a-witching-signal/1018118 "2025-05-08T19:40:31Z")\ **Posts on this page:** 15\ **Page:** 2
**Author:** ![CalMeacham](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/calmeacham/32/35_2.png) [@CalMeacham](https://boards.straightdope.com/u/CalMeacham)\ **Post date:** [May 23, 2025, 3:11pm UTC](https://boards.straightdope.com/t/what-is-a-witching-signal/1018118/21 "2025-05-23T15:11:22Z")
> [@Johanna](#): > > The only Witch in the sciences is a mathematical curve. The Witch of Agnesi, so-called, was the work of Maria Gaetana Agnesi in Italy in 1748. The explanation for its name is a groaner of a pun. The curve is what we nowadays call a _Lorentzian_, which doesn’t have a cute story to go with it. 25 years ago I made up a sweatshirt with the curve on it, subtly altered to look like the “stickmen” in the movie _The Blair Witch Project_, and labeled it **The Witch of Agnesi Project** in lettering just like that on the poster. I wore that sweatshirt to MIT and to science fiction conventions, and garnered not one commentor indication that anybody had gotten the joke. ---
**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\ **Post date:** [May 23, 2025, 3:24pm UTC](https://boards.straightdope.com/t/what-is-a-witching-signal/1018118/22 "2025-05-23T15:24:07Z")
You might appreciate the new Kicad T-shirt, then: [![](https://shop.kicad.org/cdn/shop/files/unisex-classic-tee-sand-front-67b6371d5ef62.jpg?v=1739994918) ](https://shop.kicad.org/cdn/shop/files/unisex-classic-tee-sand-front-67b6371d5ef62.jpg?v=1739994918) ---
**Author:** ![Melbourne](https://avatars.discourse-cdn.com/v4/letter/m/b5e925/32.png) [@Melbourne](https://boards.straightdope.com/u/Melbourne)\ **Post date:** [May 25, 2025, 7:48am UTC](https://boards.straightdope.com/t/what-is-a-witching-signal/1018118/23 "2025-05-25T07:48:52Z")
[Resistance is futile](https://m.media-amazon.com/images/I/51hn8HatAwL._AC_SX679_.jpg) [51hn8HatAwL._AC\_SX679_.jpg (679×832) (media-amazon.com)](https://m.media-amazon.com/images/I/51hn8HatAwL._AC_SX679_.jpg) ---
**Author:** ![nelliebly](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/nelliebly/32/5422_2.png) [@nelliebly](https://boards.straightdope.com/u/nelliebly)\ **Post date:** [October 4, 2025, 1:05am UTC](https://boards.straightdope.com/t/what-is-a-witching-signal/1018118/24 "2025-10-04T01:05:18Z")
Resurrecting this zombie thread to say that I finally got the answer! My apartment complex maintenance guy said he’d once worked on street construction. I asked him about the witching signal thing. He said the term comes from “water witching.” Apparently there are devices that can detect if there are water pipes under the pavement. He said those pipes tend to be 36 inches below the surface and so warrant markings to caution the excavators. “No witching signal” means the detector didn’t sense any pipes below. Mystery solved and ignorance fought. I really did learn a lot from all the responses, though, so a belated thank you! ---
**Author:** ![Northern\_Piper](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/northern_piper/32/5304_2.png) [@Northern\_Piper](https://boards.straightdope.com/u/Northern_Piper)\ **Post date:** [October 4, 2025, 1:34am UTC](https://boards.straightdope.com/t/what-is-a-witching-signal/1018118/25 "2025-10-04T01:34:27Z")
> [@nelliebly](#): > > Also, their spray-painting skills leave much to be desired. Kids these days! Why, back in my youth, we could spray-paint graffiti in carolignian miniscule! We took pride in out graffitti! If they can’t use a video controller, they’ve got nuffing! ---
**Author:** ![Beckdawrek](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beckdawrek/32/3647_2.png) [@Beckdawrek](https://boards.straightdope.com/u/Beckdawrek)\ **Post date:** [October 4, 2025, 1:49am UTC](https://boards.straightdope.com/t/what-is-a-witching-signal/1018118/26 "2025-10-04T01:49:48Z")
I’m so happy you got your answer @nelliebly . It bugged me too. ---
**Author:** ![DaveUnknown](https://avatars.discourse-cdn.com/v4/letter/d/94ad74/32.png) [@DaveUnknown](https://boards.straightdope.com/u/DaveUnknown)\ **Post date:** [October 4, 2025, 1:58am UTC](https://boards.straightdope.com/t/what-is-a-witching-signal/1018118/27 "2025-10-04T01:58:11Z")
Thanks for the update, I thought it was a lot more than 5 months ago! ---
**Author:** ![Northern\_Piper](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/northern_piper/32/5304_2.png) [@Northern\_Piper](https://boards.straightdope.com/u/Northern_Piper)\ **Post date:** [October 4, 2025, 2:03am UTC](https://boards.straightdope.com/t/what-is-a-witching-signal/1018118/28 "2025-10-04T02:03:16Z")
> [@nelliebly](#): > > Next time I go by, I’ll chant, “Bubble, bubble, toil and trouble” and see if a secret passageway opens Might have better luck with “[Double, double, toil and trouble](https://poets.org/poem/macbeth-act-iv-scene-i-round-about-cauldron-go).” That will probably reveal that the info you got from your maintenance guy was just a cover story, and the coven really is down below. ---
**Author:** ![nelliebly](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/nelliebly/32/5422_2.png) [@nelliebly](https://boards.straightdope.com/u/nelliebly)\ **Post date:** [October 4, 2025, 5:54pm UTC](https://boards.straightdope.com/t/what-is-a-witching-signal/1018118/29 "2025-10-04T17:54:49Z")
Ha! Once I used that quote in a (high school) freshman English class, and one of my students laughed. I asked what was so funny, and he said, “Bubble, bubble, toilet trouble! Is that a commercial?” > [@Northern\_Piper](#): > > the coven really is down below Along with the goblins. Don’t forget the goblins: > She’s gone where the goblins go > Below, below, below ---
**Author:** ![Kent\_Clark](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kent_clark/32/105_2.png) [@Kent\_Clark](https://boards.straightdope.com/u/Kent_Clark)\ **Post date:** [October 4, 2025, 10:00pm UTC](https://boards.straightdope.com/t/what-is-a-witching-signal/1018118/30 "2025-10-04T22:00:32Z")
I can’t believe no one posted the greatest witching signal ever. [![](https://www.baltimoreorless.com/wp-content/uploads/2012/08/surrender-dorothy-80s.jpg) ](https://www.baltimoreorless.com/wp-content/uploads/2012/08/surrender-dorothy-80s.jpg) ---
**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\ **Post date:** [October 5, 2025, 12:19am UTC](https://boards.straightdope.com/t/what-is-a-witching-signal/1018118/31 "2025-10-05T00:19:04Z")
I remember when that was graffitied. ---
**Author:** ![Lucas\_Jackson](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lucas_jackson/32/303_2.png) [@Lucas\_Jackson](https://boards.straightdope.com/u/Lucas_Jackson)\ **Post date:** [October 5, 2025, 3:32am UTC](https://boards.straightdope.com/t/what-is-a-witching-signal/1018118/32 "2025-10-05T03:32:47Z")
> [@nelliebly](#): > > He said the term comes from “water witching.” Apparently there are devices that can detect if there are water pipes under the pavement. Was he suggesting that the markings were made by an actual dowser? Also, have they dug up those sidewalks? The weirdest graffiti I ever saw was on a rock by a creek, which read, “Snakebite took my money”. Not a clue what that meant. ---
**Author:** ![nelliebly](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/nelliebly/32/5422_2.png) [@nelliebly](https://boards.straightdope.com/u/nelliebly)\ **Post date:** [October 5, 2025, 4:34am UTC](https://boards.straightdope.com/t/what-is-a-witching-signal/1018118/33 "2025-10-05T04:34:46Z")
> [@Lucas\_Jackson](#): > > Was he suggesting that the markings were made by an actual dowser? No. He said the archaic term is used for modern devices that detect underground pipes, a little like divining rods were used by dowsers, aka water witchers, to (supposedly) detect underground water. I know two of the sidewalks that were marked were dug up and repaired. I haven’t been by the others for quite awhile, so I’m not sure. > [@Lucas\_Jackson](#): > > "Snakebite took my money”. 😆 ---
**Author:** ![Really\_Not\_All\_That\_Bright](https://avatars.discourse-cdn.com/v4/letter/r/e8c25b/32.png) [@Really\_Not\_All\_That\_Bright](https://boards.straightdope.com/u/Really_Not_All_That_Bright)\ **Post date:** [October 5, 2025, 11:39am UTC](https://boards.straightdope.com/t/what-is-a-witching-signal/1018118/34 "2025-10-05T11:39:26Z")
Drink enough of them and you’ll find out! ---
**Author:** ![HMS\_Irruncible](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/hms_irruncible/32/7394_2.png) [@HMS\_Irruncible](https://boards.straightdope.com/u/HMS_Irruncible)\ **Post date:** [October 5, 2025, 12:33pm UTC](https://boards.straightdope.com/t/what-is-a-witching-signal/1018118/35 "2025-10-05T12:33:31Z")
> [@Napier](#): > > I wonder if it might be related to “water witching” or “dowsing”, a practice claimed to find good locations to drill water wells? At least when I bought my house between Baltimore and Philadelphia forty years ago, belief in dowsing was strong enough that water witches were often hired. In fact the volunteer fire department nearby is the “Water Witch” fire department. Perhaps somebody marked some spots that a water witch said they got a signal? Sounds like Napier had the right idea, if not the exact mechanism. [Previous page](https://boards.straightdope.com/t/what-is-a-witching-signal/1018118.md?page=1)