On the southern slopes of the Sperrin hills is a place called Beaghmore from the Irish an Bheitheach Mhór (The Big Moor of Beech Trees) and on a flat piece of ground you will find the Beaghmore Stone Circles, one of the circles is known as Fiacla Dragan or Dragon’s Teeth. The inside of one circle is filled with small sharp stones.
Now the main character in this story is Finn MacCool’s wife, she went by the name Sadhbh which has way to many consonants for English speaking tongues but is pronounced “Siive”. Many are the stories of Finn and his son Oisin and they are famous for their acts of bravery and “Getting things done” , but if truth be told they were a bit “Nice-but-Dim” , or if you will not that sharpest crayons in the box 
Now in the MacCool family the wit and charm went on the distaff linage, and Sadhbh held true to this rule. She was a sharp as a gorse bush thorn and as quick as fox in a hen house.
Now Sadhbh lived in the family home with Finn and Oisin up on the north coast but her family were from down near the modern Cookstown in Tyrone. She went to visit her relatives one weekend and when she arrived she found the village in turmoil. Because the Queen of the Dragons (called oilliphéist in Irish) Caoránach (which means Coal) had been terrifying the village and the surroundings. Now in Ireland Dragons like Caoránach are pretty much like Dragons in the rest of the world, bad tempered greedy and partial to munching on the occasional virgin. I have to add at this point the Dragon’s name was not Caoránach that is what people called it and it was named after the colour of its scales which were as black as coal…What a dragon called itself was a secret .. because a dragon’s real name when spoken was the most powerful magic !
Sadhbh took the news of this disaster that had stuck the place she grew up in her stride and when told when “Pfffffftttttt it is just a big Snake”.
It being a nice summer day, she got a tankard of ale and wandered out into the field and rolling up her skirt to get the light of the sun on her legs she lay down on a hay bale and waited.
She did not have to wait long, the dragon appeared and swooped and roared fire and did all the things you would expect a dragon to do, it usually impressed the fuck out of people, but Sadhbh just sat on her hay bale and sipped her ale.
The Dragon landed close by and fixed Sadhbh with a gimlet gaze calculated to put the fear into the stoutest hearts. The Dragon was over 1000 years old and this gaze had never failed her … until now.
“Hello there ” said Sadhbh
“Cower woooooooman for I will eat you virgin or not!” hissed the dragon.
“Pfffft ” said Sadhbh “I perfer to drink my beer and get a bit of tan on the legs. My husband Finn MacCool likes to see my tan lines and who am I to begrudge my husbands foibles”
The dragon took a step back, looked around and asked “You are Finn MacCool’s wife?”
“Why yes i am Sadhbh MacCool and never fret he is not here he is off doing something heroic and quite possibly dangerous and very likely the bards will sing about it in the years to come …. he does that and very good at it he is .. but send him to get butter and eggs from Mrs McMaghon down the road and he will come back with a donkey and an new turf spade!”
The Dragon considered this for a while.. smoke drifted from each nostril. Eating Finn MacCool’s wife might just be a bad thing to do, but would some non-fatal injuries be do-abe?
“So Mrs Dragon i hear the people call you Coal because you are so black .. must be annoying that , it would be like you calling me Wheelbarrow because I do a lot of gardening, Now I wonder what you call yourself?”
The dragon took a step back a look of profound worry on its scaley face. “No-one knows my real name NO ONE!” it roared!
Sadhbh was unimpressed and told the dragon so. “I do not think there is anything you can do to impress me, remember I am married to the man who made the Giant’s Causeway because he did not like the singing coming from Scotland!”
The Dragon thought for a while took off and in one long swoop burnt an entire stand of mature Beech Trees. She flew back and when “Well what about that!!!!”
“Pffttttt I have seen Finn beat an entire army of demons with nothing more than Soup Bone and a wee spoon”
The dragon thought some more .. “Well” it said “Give me something to do and I will do it 100 times and more”
Sadhbh thought for a moment and said .. “Use your jaws to break that big stone over there” she pointed at a menir in the corner of the field.
The dragon laughed and went to the stone … it lifted it in one hand tossed it in the air … and opened its maw and as the stone fell she saw in horror that etched in the stone in Ancient Ogham script was her real name ……. “Tracy” I know not a particularly Irish or indeed Dargonesque name, but you cannot help what your parents call you,
The stone landed in the dragons mouth and as it did Sadhbh muttered “Tracy looses her teeth” and as the dragon’s jaw closed the stone broke every tooth in her head.
Sadhbh got off her bale and wandered over and picked up one of the smaller teeth and put it in her apron pocket. She turned to the dragon … “It is best..” She said “To know what people call things, on the day you hatched and your mother called you TRACY .. dear gods what was she thinking … a druid was near by, heard the name and carved it on that stone and buried it. For a 1000 years that stone has been called DRAGON’S BANE now if you had spent just a while getting to know the people that lived here rather than eating them ,you would have known that.”
Sadhbh leaned forward and tapped the Dragon’s now toothless mouth. “Tracy, time for you to get away out of here.. and Tracy I wouldn’t come back, Find somewhere where there are no people, because you know us humans we love to talk and it will not take long for everyone to know your real name”
The Dragon took off and flew to the west , farther and farther, it is said she flew to the misty lands of Tir an Og and is there to this day.
The locals laid the teeth in a circle and there are there to this day.
And that is the story of Sadhbh and Tracy the dragon