SCHOOL: Baile an Bhile | ADDRESS: Ballinvilla Demesne, Co. Mayo

When Saint Patrick was banishing the serpents from Ireland the king of the serpents came to him and told him that he would call all the other serpents away from our island if he allowed the largest to remain. The saint was pleased with the offer and the bargain was made.
Then the king of the serpents called all the others away except the largest who had his dwelling on the shores of Mannin lake which lies to the north of Bekan Claremorris.
After a time St Patrick came to Holywell, Ballyhaunis. He heard the people of the district tell how the serpent was stealing and devouring cattle and sheep belonging to the people of the neighbourhood. St Patrick resolved to banish him also.
He went to a blacksmith who lived near where the town of Ballyhaunis now stands. The blacksmith’s name was Mannin. He ordered him to make an iron chest with nine bolts on it. When it was made he brought it to the lake where the serpent had his abode.
When the serpent saw him coming he began to hiss and show his teeth.
St Patrick bade him not to be angry and told him that he had brought him a nice house for the winter. The serpent began to complain of the house being too small.
“I’ll bet you a gallon of porter that it’s not,” said the Saint.
The serpent was very thirsty and he swelled himself up as big as he could and entered the chest all to a wee bit of his tail.
“Now St Patrick pay me my gallon of porter,” he said.
But St Patrick raised the lid aloft and let it slap down on the chest.
The serpent pulled in his tail when he saw the lid falling and St Patrick began to fasten the bolts.
The serpent began to roar so much that all the fish in the lake died with fright. Then St Patrick rolled the chest into the lake.
It is said that it is the struggling of the serpent that causes the whirlpool in the lake.
St Patrick then remembered Mannin and called the lake after him.
Bibliography
“The Schools’ Collection, Volume 0110, Page 004” by Dúchas © National Folklore Collection, UCD is licensed under CC BY-NC 4.0.